The Bees of the Eastern United States, Introduction, Mitchell 1960

These have reached a state of completion which suggests the desirability of their pub- lication, even though new records a r e still being made and new species discovered.. I t is hoped

Foreword

This monograph is t h e culmination of 313-

proximately 38 years of collecting a n d re-

search on t h e taxonomy of our native bees

Interest i n t h i s group w a s first incited dur-

i n g my employment i n t h e K o r t h Carolina

Department of Agriculture, where one of

t h e projects was t h e compilation of t h e list

of insect species known to occur i n K o r t h

Carolina The list of bee s ~ e c i e s accumu-

lated a t t h a t time (1920) \vis quite small

including only about 60 names, and many

of these records were obtained f r o m t h e

literature r a t h e r t h a n f r o m collections made

b y t h e personnel of t h e Department Initial

collections resulted in many additions to

this list, but with a considei.;:ble propor-

tion unidentifiable, due either to the in-

adequate keys then available o r t o t h e

Iiumerous apparently undescribed species

t h a t were found This presented a challenge

;ind a s a result, t h i s g r o ~ ~ p of insects h a s

become my chief interest and a n expanded

lrno\vledge of t h e group a primary objective

Beginning with these earlier experience

m y associates have influenced my life and

professional development Certain of these

stand out in memory a s having been es-

pecially influential, and f o r whatever has

been accomplished, some of the cl.edit a t

least, belongs t o them The head of t h e

Division of Entomology a t t h a t rime ~\.:li

Franklin Sherman Aside f r o m t h e reguln-

tory, extension and economic research nc-

tivities then carried O I I by t h e Dilision, hi<,

main interest 1v:is t h e compilation of t h e

North Carolina insect list, and in co1i.e-

quence h e gave enthusiastic support and

encouragement t o t h i s study of our bee

fauna C S Brimley was i n t h e employ of

t h e Division, devoting his time to t h i s list

H e w a s a natura!ist of t h e old school, large-

ly self-taught, with broad interests arid ex-

tensive knowledge of such diverse group\

;is birds, reptiles, amphibians, moths,

flies, wasps a n d many other groups of in-

\ects H e was a philosopher a s well and in

h i m was found a close friend and a compali-

ion on many collecting excursions through-

o u t Il'orth Carolina I n 1922, J C Crawford

loined t h e Ilivision, coming f r o m t h e U S

S a t i o n a l Museum H e n ,i> a n exl~eriei~cecl taxonomist and had done consiclerable worIc

on t h e systematics of bees, a s well a s other groups F r o m t h i s associatioll IT a s derived much of value, including :L better under- standing of certain of t h e basic principle\

of taxonomy Alan)- of t h e ideas and tech- niques acquired a t t h i s time influenced my work d u r i n g t h e later years

I joined t h e teaching staff of t h e Depart- ment of Zoology and Entomology a t North Carolina S t a t e College i n 1025 The late

Z P Metcalf, Head of the Department, m-.;a<

a n authority on t h e Order Homoptera :~ntt

a n enthusiastic taxonomist with a world- wide reputation To h i m I a m deeply in- debted f o r assistance and xvol.ds of advice,

f o r encouragement and s ~ ~ p p o r t , and f o r u e n ideas and techniques The association lasted

f o r more t h a n t h i r t j ye;\rq until his death and throughout t h i s period complete free- dom as enloyet1 in t h c performance nf teaching duties and research activities - T l i

t h i s assignment t h e suninlei month.: wer' available f o r resea1.r.h kind f o r xdvanccd study This included h t ~ ~ d i c at I31issey 111-

s t i t u t e of H a r v a r d L-~:i\el it> \vhere t h e r r - search was carried on under t h e direction of

V' M Wheeler a n d C T C!.lie-; This asso- ciation with these two out: t n t ~ d i n g teacher\ served to augment my iiitereit and e:1- thusiasm f o r taxonomic research

U u l i ~ ~ g t h i s period one u f t h e ge::el.L uf bees, l I ~ g u c h i l e , was selected f o r hpccial :it-

tention A revision of t h e S o r t h Americ;~ii species was prepared and p n b l i ~ h e d , nit11 some attention given t o t h e species of sc me

of t h e other regions of t h e ~ ~ o r l c l Ho\x;ei el :ill collecting was general, so f u ,IS t h e bee,

a r e concerned, and much n ~ ~ t e r i : , l was a c -

~ ~ ~ m u l a t e d , w i t h distribution a d host rec- ords inclucted While t h i s collcc i irig n as in progress, n bibliogr:~pl~)- w a i belilg conl- piled A photographic method of cop: ing t h c literatu~.e, using 33 mm film, xa.: devel- oped before i t came into t h e general ube

it has today

D u r i n g t h i s Linlt , .Llno, he).> f o ~ ti111 1 c i t 1 1

t ~fication of t h e specie.; ,if I.ee gvenpr.l

4 BEES O F THE EASTERN UNITED STATES, 1

were gradually developed and perfected

These have reached a state of completion

which suggests the desirability of their pub-

lication, even though new records a r e still

being made and new species discovered

Actual completion of such a comprehensive

study as this one is a "will-o'-the-wisp," and

there comes a time when i t is best to publish

what has been accomplished, in order to

make the results available to other workers

I t is hoped that publication of these keys

and descriptions will facilitate more inten-

sive studies of the taxonomy of bees, a s well

as ecological, biological and economic stu-

dies of all of the included groups

One very important phase of this re-

search has been the study of type collec-

tions in the United States, Canada and Eng-

land I am indebted to many individuals in

various institutions f o r assistance in the

location of type specimens, for providing

facilities for their examination, and f o r

freedom of access to the collections Among

those that should be named a r e Herbert F

Schwarz a t the American Museum of Na-

tural History in New York; I II H Yarrow

a t the British Museum (Natural History)

in London; G C Varley of the Hope Mu-

seum a t Oxford, England; H H Ross,

B D Burks and &lilton W Sanderson a t the

Illinois Natural History Survey in Urbana,

Illinois; E T Cresson, Jr., James A Rehn

Katural Science of Philadelphia; Noel M

Comeau a t the Provincial Museum a t Que-

bec; the late 1Gatha:i Banks, Joseph Be-

quaert and Wm L Brown, Jr a t t h e Mu-

seum of Comparative Zoology a t Harvard

University; and C F W Muesebeck, the

late Grace Sandhouse, and Ka1.l V Krom-

bein a t the U S National Museula in

Washington, D C I am especially indebted

to K W MacArthur a t the Public Museum

of Milwaukee, Wisconsin, and H G Rodeck

a t University of Colorada Museum, for

lending several t; pe specimens, and to Har-

vey B Lovell of the University of Louisville

for sending the entire type collection of his

father, the late John H Lovell Through the

cooperation of Arthur Humes, of the De-

partment of Biology of Boston University,

and a t the suggestion of Wm L Brown, Jr.,

several of the Viereck types of Andrena

formerly in the collection of t h e Boston

Society of Natural History, that were tem-

porarily lost, have been found and a r e now

in the Museum of Comparative Zoology

A large amount of undetermined material was received from several of these same institutions a s well a s from a number of others Such collections have been received from Henry Dietrich and Howard E Evans

a t Cornell University; T H Hubhell and

U K Lanham a t the University of Michi-

g a n ; Roland Fischer a t Michigan State College; J N Knull a t Ohio State Univer-

s i t y ; H E hIiIliron a t the Ulivcrsity of Minnesota; Herbert I<nutson a t the Unirer- sity of Rhode Island; J T hfedler a t the University of Wisconsin; B Elwood Mont- gomery a d Leland Chandler a t Purdue University: Howard V Weeins, Jr., Frank

W Mead and Roger A Morse of the Florida State Plant Board; and D I, Wray of the North Carolina Department of Agricult1:re Personal collections have been received from Henry K Townes, G E Eohart, Karl V

Krombein, R R Snellii~g, H F' Howden and wife Ann, C I) Michener, and exten- sive amounts of unidentified materials from

R R Dreisbach of Midland, Michigan, and the late P W Fattig of Emory University The author is indebted to Mrs Sylva G

Martin of South Miami, Florida f o r the

g i f t of a considerable proportion of the collection of her father, the late S Graeni- cher

Several taxonomic specialists have given valuable assistance P H Timberlake, of Riverside, California identified all of the

material in the genus P e ~ d i i a , which he is revisicg, and described all of the new spe- cies which were discovered in the eastern col~ections I am grateful for his assistance and for t h e promptness of his attention to the material and to publicatioii of the n e x names, making them available for this u-orlr W P Stephen, nov? a t Oregon State College, revised the genus Colletes while pursuing graduate studies a t the University

of Kansas All of our eastern material \>,-as submitted to him for study Similarly, Wal- lace E LaBerge, now a t Iowa State College,

revised the genus Melissodes while a t the

University of Kansas, and our eastern ma- terial was sent to him also Currently (April, 1958) A F Shinn is making a re-

visional study of Calliopsis a t ti?e Univer-

sity of Kansas and has our material of the few species of this genus that occur east

of the Mississippi

In addition to assisting in type studies

a t the U S National nluseum and furnish- ing collected materials, Karl V Krombein

has read portions of t h i s nldnuscript and

has tested t h e more comprehensive keys A -

a result he h a s been able t o make helpful

and constructive criticisms Sirnilar coil-

structive criticism h a s also bee;? received

from David A Young, F r a n k E Guthric

Maurice H F a r r i e r , Walter M Kulash, and

Clyde F Smith, associates in t h e Depart-

ment of Entomology a t North C:L1.oiin:l

S t a t e College

I am indebted t o Mrs Violet Quay a:ld

Miss Mary Oliver Ei1ingr;on f o r a portion

of the illustrations

Also I wish to express my appreciatioll

to t h e Administrative Officers of North

Carolina S t a t e College f o r their sympathetic

a t t i t u d e toward t h i s research and f o r thrb

provision of funds, without which t h e work

would not have been possible Throughout

t h e many years of my association with Z P

Metcalf, t h e r e existed i n t h e Department of

Zoology a n d Entomology, a "clirnate" con- dusive t o research activities, and t h i s has

c o ~ t i n u e d to t h e present time under t h e chairmanship of Clyde F Smith This same sympathetic a t t i t u d e i s evident i n t h e suc- cession of higher administrative officia!~,

a t l d t be mor:ii and fin'lncial support of D B Anderson, Chairman of t h e Division of Giol- ogv, Roy L Lovrorn, Direc~tor of t h e Ex- periment Station, D W Colvard Dean of

t h e Schoc.! of Agriculture, and C W Eos- tian Chancellor of t h e College i s here ac- k~:o~v'edged with appreciation

I'inally I wish to ~ c k r ~ o w l e d g e my debt t o

t h e n'ntionnl Sciellce Fozi?zdntion, f o r f u n d s

tc, support t h i s work and to provide f o r i t s publication, a n d I a m appreciati7:e of t h e

h e i p f t ~ l suggestions, first of Rogers Mc- Vaugh a n d later of A C S m i t h a n d David

I) Keck, i n t h e performance of t h e i r func- tions a s successive P r o g r a m Directors f o r Systematic Biology

T B Mitchell

Professor o f Entomology

N o r t h Carolina State College

Materials and Methods

The superfamily Apoidea of t h e order

Hymenoptera comprises t h e group of in-

sects commonly called bees The group is

closely allied to the sphecoid wasps, with

many characters common to both I n some

schemes of classification t h a t have been

proposed (Comstock, 1940) they a r e com-

hined into one snperfamily, the Sphecoidea

In most recent texts, however, such as

Brues, Melander & Carpenter (1954) ; Bor-

ror and DeLong (1954) ; and in the recently

published catalog by Muesebeck, Krombein

Townes, e t a1 (1951) ; the Apoidea is recog-

nized a s a superfamily group, separate from

the Sphecoidea As a matter of convenience,

the separation of the t ~ o seems desirable

but the fact t h a t the sphecoid wasps a r e

much more closely related to the bees than

they a r e to the vespoid wasps or any of the

other Hymenoptera should not I)e overlook-

ed

The bee fauna of the Eastern United

States has hitherto not been fully described

Many species new to science will be de-

scribed in this monograph, and doubtless

others will still remain to be discovered by

collectors in the future Furthermore, many

species a r e known in only one sex, and only

more intensive collecting, field observations,

or studies of the biology will make i t pos-

sible to discover the unknown sex or to

currelate the two when they have been de-

scribed under separate names There is a

current i ~ l t e r e s t in biological and ecological

studies of bees, but with respect to the total

number of known species i t is a n almost

virgin field, with a relatively small propor-

lion in which any studies a t all have been

1)ublished A review of this field of research

has been published by Linsley (1958) There

is a considerable fund of host plant data,

largely from the works of Charles Robert-

son, J C Crawford, John H Love11 and S

Graenicher, but there is much yet t o be

learned The importance and significance of

flower records, in the collection of bees, can

hardly be overemphasized Most of the pres- ent generations of specialists in the group

a r e keeping such records, but most of the earlier colIected specimens lack any refel.- ence to host and specimens of bees collected

by specialists in other groups often lack such data

Bees a r e essential to onr economy, being the chief pollinating agents of the flower- ing plants They have a relation not only to agriculture, but to the conservation of xviltl- life and game management, and constitute

;in important element in the various eco- logic factors t h a t combine to form our ell- vironment Thus t h e productic~n of f r u i t rrops such as apples pears, melons, cucum- bers, grapes, dewberries, huckleberries aild qtrawberries, a s well as cotton and various seed crops such a s alfalfa, several clovers vetch, onion, asparagus, buckwheat and celery, a r e dependent upon a suflicient popu- lation of bees, either the domesticated honey bee or some of oul- native wilil, qolitary or social species

Much reliance often is placed upon the honey bee in agricultural production, to compensate f o r a lessened effectiveness 01-

unreliability of the native bee species The growth of agricultural crops creates :in artificial environment which often is un- favorable to the development of the large populations of native bees t h a t a r e needed

f o r adequate crop plant pollination Nest- ing areas of solitary bees a r e plowed u p ,

brush and weeds a r e cleared from roadside5 and ditch banks, woods a r e cut or bur~lect over and t h e underbrush eliminated 1'i1( plant population w h i ~ h extensive ;ccr.eugtJ\

of a crop represents is abnormally largc, being a pure stand of a species which prol)- ably did not develop a s such in its oyiyinal native habitat Thus its insect enemies tend

to multiply, being relieved of one of the most important limiting factors, t h a t uf food supply With bees, however, i t seems possible t h a t the availability of nesting site5

is more of a limiting factor than food s ~ r p -

8 BEES O F T H E E - ~ s T E R N U N I T E D STATES, 1

ply, w h i c h m a y be a partial explanation f o r

t h e dearth o f native bees i n m a n y crop

areas Fortunately i n m a n y cases t h e intro-

dvrtion o f honey bees ofFers a rather simple

sc.1~1tiou t o t h i s problem a,:d there has not

been too m u c h concern about t h e lessened

numbers o f native bee species w h i c h seems

t o be i n evidence Some studies however,

indicate t h a t native bees are more eKcctive

pollinating agents t h a n t h e honey bee with

respect t o certain crops, such as a l f a l f a

Studies have been i n progress f o r some t i m e

concernil~g possible means of a m p l i f y i n g

populations o f certain lenfcutter bees and

alkali beer i n t h e a l f a l f a seed-pi-9drci1:p

areas

T h e native bee fauna probably i s m u c h

more i r n p x t a n t t h p n t h e hbne.r be? i*i thr:

conservation o f wi!d l i f e and game man-

agement, even t h o u g h m a n y wild colonics

o f honey bees occur i n m o s t wooded areas

Game birds, such :is quail and t u r k e y , t h e

song birds, and marly o f t h e mammals de-

pend t o a considerable e x t e n t upon t h e

f r u i t s o f various native plants, and such

plants have a m u c h closer ecological rela-

tionship t o t h e native bee f a u n a t h a n have

m o s t crop plants

Bees constitute a group o f considerable

size, w i t h about 700 species listed f r o m t h e

eastern United States b y Afuesebeck, Krom-

bein, Townes, e t a1 ( 1 9 5 1 ) T h e r e i s m u c h

variety o f f o r m , size, color and habit w i t h i n

t h e group, w i t h social types, represented

b y t h e honey bee and t h e bumble bees, and

solitary t y p e s which include t h e large ma-

jority o f species A m o n g these solitary spe-

cies are ground burrowing and woodboring

f o r m s , as well as a considerable n u m b e r

-which use a n y burrows, borings, or other

types o f cavities t h a t m a y be available

T h e r e are also m a n y cuckoo or parasitic

species which invade t h e nests o f pollen-

collecting t y p e s t o lay t h e i r eggs, m a k i n g

no other provision f o r t h e i r young

T h e f a c t t h a t our knowledge o f bees as

a group i s inadequate i s not t h e only difficul-

t y t o be encountered i n a t t e m p t s a t identi-

fication o f species or determination o f a n y

possible economic e f f e c t or ecologic signifi-

cance Comprehensive or adequate k e y s t o

t h e species o f m a n y o f t h e included genera

are not i n existence, and t h e descriptions

o f a considerable proportion o f t h e k n o w n

species are widely scattered i n t h e litera- ture Moreover, descriptions w h e n available are o f t e n so b r i e f or incomplete t h a t t h e y are o f little value i n making reliable identi- fications T h i s common inadequacy o f de- scriptions should not be t a k e n as implying

a n y inadequacy o n t h e part o f t h e workers,

b u t i s more t o be considered a reflection o f

t h e degree o f development o f t h i s field o f science at t h e t i m e these workers w e r e ac- tive I t i s quite possible, i f not probable,

t h a t t h e work o f t h i s present generation will be found t o be quite deficient i n certain respects b y workers i n t h e f u t u r e

Objectives

T h i s i s a faunal s t u d y o f t h e bees o f t h e United States east o f t h e Mississippi River

I t i s com11l.eheneive w i t h respect t o t h e cov- crag,: o f t h e group, including all t h e f a m i - lies, genera and species o f bees, b u t i s limit-

ed geographically, so t h a t no generic or other group i s covered completely unless i t has these same geographic limitations

T h e primary objective i s t o facilitate identification, and t o t h a t end simplicity o f keys i s sought T h u s all keys are artificial and are not intended as a n expression o f phylogeny T h e use o f couplets o f contrast-

i n g characters i s strictly adhered t o , and

t h e m o s t conspicuous characters available are employed, sometimes t o t h e exclusion

o f more obscure features w h i c h m a y be o f greater phyiogenetic significance

T h e rather detailed descriptions and t h e figures should serve as a check respecting

t h e correctness o f identifications made b y

t h e use o f t h e keys

Geographic Area

T h e states o f Wisconsin, Illinois, Ken-

t u c k y , Tennessee and Mississippi, and all others east o f t h i s t i e r are included i n t h i s work T h i s arbitrary division is approxi- mately t h e 92nd meridian and all o f these states lie t o t h e east o f t h e Mississippi Riv-

er I11 large part, i t i s t h e Austral Region,

b u t t h e Canadian i n t h e Boreal Zone i s in- cluded, and a t t h e southern end o f Florida

t h e subtropical region is reached

Collecting Techniques

I n collecting bee., nets a n d killing bottles,

of cour\e, al.e essential items o l equipment

The ~ ~ r i t c ' h a s f o ~ m d th a t n relatively

short-bandlei1 net ~ i t h >I r i n g not more

tharl 12 inchrs i n dialnetel is p r e f ~ r u l ~ l e

a longer-hoxiiiled o r larger net A smaller

net w i t h t h e shorter h;,ndie car I-lc slvung

more rapidly t h a n a l a r p c i one, a n essential

fe:,t~l;.e in c ntching ~i1:11ly of t h e bees t h a t

ha7,e rapid flight Gecauie collectiag on

trees or high hushes necessit;,tes a reason-

ably long handie, i t i- nil a d r a n t n g e t o h a ~ e

a j o i n t 4 o r telescoping handle, or t o have

a longer substitute handle o r net

The collector should have a considerable

number of killing bottles so t h a t specimens

collected f r o m various plant species t h a t

may be i n bloom a t t h e same time may be

kept separate I t is well to have a vasculum

o r plaxt press so t'nat plant specilnens which

a r e needed for identification rnay be collect-

ed I n aclt?ition, p ~ i i boxes for t h e temporary

reception of co!!ected materials and pinning

boxes in which they may be pinned while

still in t h e field a r e also a n a c t ~ a n t a g e

Collecting often requires considerable

patient watching of plants i n bloom i n or-

der to observe some of t h e r'lpidly flying

insects t h ~ t l i b i t them This is particularly

t r u e of marig of t h e maiea which may not

be visiting t h e bloom f o r feeding purposes

but rather a r e looking f o r t h e females In

such case they rclrely alig-ht on t h e blcom,

and they can only be co!lected by sudden

and s n i f t svb7eeps of t h e net Sweeping of

the flower heads of relatively dense patches

of flonrering plants will sometimes yield

good results, but often such movements will

result in driving off some of t h e bees in ad-

vance of the collector

I t is essenti:~l th a t t h e liilling bottles be

kept a s clean :IS possible A small amount of

absorbent material i n t h e bottle mill pre-

vent t h e accumulation of enough moisture

to m a t t h e pubc.scent col-ering of t h e speci-

mens This is especially important i n collect-

ing bees because these insects often regur-

gitate nectar while dying i n t h e cyanide

gas The writer uses shell vials of about a n

inch in diameter Number 4 neoprene o r

rubber stoppers a r e used A 14 mm hole i s

bored through t h e center of t h e stopper, a n d

a I - g r a m lip vial is fitted into the hole with

t h e open end do\vnrvard The vial is partial-

l v filled with calcium cyanide o r sodium cyanide, plugged w i t h a wad of cotton, and the charged stopper is p u t into t h e shell

1 ial The cyanide may be slow to act n t first,

b u t a f t e r a f e w specimens have been placed

in t h e killing bottle i t will become e r e c t i r e Sodium cyanide will remain a c t i l e f o r a loager period t h a n t h e calcium cya.~ide, b a t otherwise t h e two a r e equal!y en'ertive Eubber stoppers a r e much to be preferred over those of cork f o r they do not crack, and t h e i r pliability i s a n added advantage n'hen t h e cyanide becomes inactive t h e vials can be emptied easily and a f r e s h charge installed Granular cyanide is used, with no plaster of I'aris o r any other material o t h e ~

t h a n t h e cotton plug

Preparation of Specimens

I n pinning specimens i t is quite impor-

t a n t t h a t t h e central a r e a of t h e scuturn be avoided s? f a r a s possible If t h e pin i s placed t o one side of t h e center, t h e sculp-

t u r e of t h i s a r e a is not destroyed Very small specimens can be cemented t o points

or directly to t h e side of t h e pin When cementing t o t h e pin, t h e speciiilen is placed

on i t s left side w i t h t h e head do\vnwarcl and

t h e legs toward t h e left A sniall amount of cement is placed a t t h e proper point on t h e pin which is then prcssed firmly t o t h e side

of t h e specimen, holding t h e head of t h e pin

i n t h e r i g h t hand T h u s t h e specimen will

be cemented on t h e left side of the pin with

t h e head directed forward Before speci- mens have completely dried and hardened i t

is desirable t o pull t h e proboscis out into a n extened position and t o spread t h e mandi- bles a p n r t so t h a t t h e dentition and t h e fea-

t u r e s of t h e labrum beneath m a y b e obserr-

ed I t may be necessary to s t r a i g h t e n out

t h e legs, so t h a t they do not cover t h e lateral

o r ventral surfaces of t h e t h o r a x and t h u s obscure t h e surface features of these parts While male specimens a r e still f r e s h and pliable, t h e genital a r m a t u r e should be pull-

ed out into a n exposed position T h e hidden apical sternal plates of t h e abdomen of t h e males also a r e of considerable importance Collection d a t a on t h e record labels shogld include t h e locality, d a t e of collection, name

of collector, a n d whenever possible, t h e generic identification of t h e plant upon which i t was collected T h e specific identity

of the plant host seems to be less important,

I ~ L I ~ sometimes is o f iignific:~rice EIowe\el.,

identification of species i n home genera of

plants, huch a s RIIOVS, A s f r ~ , Solidago and

others, is difficult even f o r many botanists,

and i n such groups especially, specific iden-

t i t y i s of slight importance

If any spec.imens a r e collectecl a t some

r~nusual t i m e of day, a s early i n t h e morn-

ing o r a t rlusk, or if they ;ire found i n light

t r a p s 01- nt baits, s~1c.h informatior; should

1)e incl~ided on the ~ c r o r d label

Source of Materials

3Iuch of tlic material upon which this

study is based was collected by t h e w r i t e r

1;irgely in S o r t h Carolina Of all t h e eaqt-

ern states, probably i t has t h e most diverse

~ l i m a t i c ancl ec-ologic conditions, such a s to

duplicate to a considerable degree condi-

tions f r o m Maine t o Florida along t h e en-

t i r e Atlantic Coast A t the high& e l w a -

tions extensions of t h e Canadian Zonc a r e

met, while along t h e coast t h e Austrori-

parian Zone extends t o North Carolina and

Virginia Only t h e southern t i p of Florida

with i t s possible West Indian aftinities

ieenis u n ~ e l n t e d to North C i ~ ~ o l i n : ~ fauniq-

tically

Collecting has been done also i n JIaine,

Massachusetts, Illinoiq, West Virginia,

South Carolina Georgia and Florida Many

records have been obtained through t h e

htudy of collections t h a t h a r e been sent to

the a u t h o r f o r identification T h e w have in-

cluded much material f r o m New England

E a s t e r n Canada, New York, Michigan, Wis-

consin, Minnesota, Illinois, Indiana, Ohio

Maryland, Virginia West Virginia, Tennes-

iee, Georgia and Florida, with lesser

t h e Mississippi

Type collections t h a t have been studied

i~iclutie th e Frederick S m i t h collections in

the British Museum :ind in t h e Hope Mu-

ht.urri ;\t Oxforcl University; t h e Provancher

(ollectiot~ i n t h e Provincial Museum of Que-

I)ec; t h e Cresson collection i n t h e Philadel-

phia Academy of Science, t h e Robertson

collection in t h e Illir~ois N a t u r a l History

Survey ; ant1 types of Cockerell, Viereck,

('rawford a n d others i n t h e United States

National Museum; t h e American Museum

of Natural History i n New Y o r k ; t h e M u -

wurn of Comparative Zoology t t H a r v a r d ;

t h e ('c~nnecticut Agricultural Experiment

S t a t i o i ~ 2nd t h e T9ublic M ~ ~ s e u m of Milmall-

kee The Lovell types temporarily a r e i n

t h e possession of t h e author A f e w of t h e Linnaean, Fabrician and Vachal types ha\re also been studied

Taxonomic Methods

All existing keys ancl published descrip- tions were used, of course, i n t h e initial stages of t h i s study L a t e r these mere sup- plemented by examination of t h e types, and the identity of most of t h e species so f a r recorded in t h e E a s t h a s been verified by c.ompa~isnn of specimens with t h e types

As t h e ~r-ork progressed, more and more forms came to hand \\-hich were i n need of name and description These were tempo- l.:trily signed numbers in lieu of names and keys were c o n s t r ~ ~ c t e d t o include these along with all t h e previonqly known species These provisional kevs were especially use- ful in t h e study of type collections, a s t h e types c<ould be traced through t h e key a n d then compared with t h e forms to which they appeared to run I f , i n this comparison, t h e tlegrec of similarity was such a s t o indicate their common identity, t h e specimens were made homotypes and served a s a means of comparison in type studies of other collec- tions

The finished keys a s they a r e presented

in t h e following pages, were produced f r o m these provisional keys by a process of de-

T elopment and testing followed by revision and retesting until a \vorkable key was achieved Most of them have been in a process of ilevelopment f o r a period of sev- eral years

I n large genera, such a s A > l d ) ~ n a , t h e hpecies a r e separated out i n one comprehen- sive key, even though subgeneric groupings

of these species have been proposed The limits of these subgenera sometirr:es :ire poorly defined, a n d t h e characters separat-

i n g them a r e often difficult t o observe o r interpret Well defined subgeneric groups inay eventually be recognized a s valid gen- era, b u t such modifications of t h e classificu- tion a r e dependent upon revisional and ex- tensive studies of these large genera throughout their range

All included species, both old anci new,

a r e described a s completely as seems neces-

s a r y t o establish identity, with t h e aid of

t h e key:; T h e redescription of older specieh

is desirable because of t h e freqiient in-

adequacy of Ihc origi i i ; t i cli:qc ~ i p t i o ~ ~ < , iintl

new species of coi.il.se, ;ire tlc.sci.ibzd of

necessity The de:iirnbiliiy of including de-

scriptions of spccic.s \~-!:ich ll::< ! Ilct.11 i l p -

scribed in recent y(!;~rs :II:(? ;t t~ i l l C , J ~ ! S C -

cluence relatively complcti: migkit I)? clues-

tioned but i t i s be1ievi:d t h a t !l?c ~ i r l \ - ; r ~ ~ t u ~ ~ t ~

gained i s worth t h e st!,.^ :sp;~c- i1;ivint

these clescriptior~s inc,lridr:l ~ c ' ~ a i t ; i t ] ;! ;:.if-

sufficient n-ark, rc:li<~;-ing it :rse~., oi' t i i t )

necessity of refei'ring to c ~ t ' l ~ r p~!l~iic;!tiot~s

which i s a m a ~ k c c l ntlrantnre i n c\)ilsirle?;l-

tion of t h e extent o f t h c :iti~1.2tti!.il t h a t

o t h e r ~ v i s e ~voultl bc involved

Illustrations of signiiicaant sti.;:c.i!,i,;il tlcx-

tails a r e very 11si.fu1 ;i!~tl fiyli~,c- -ho:'-ii~c

these f e a t u r e s a r e pi.ovided ;is ~i p~11.i o f !;I(,

tlescription So!, most spccies I n mnl:.~, IIIV

genital itrn?atl:rc and te!cscc~pcil scve~:th

and eighth s++.rnnl 1)l;iti.s :ire i mpor1:i;:t i I:

t h i s regard This :;eye.csit:itcs cli:isec!i!~g

these p:irts o:it ?)f t h ~ ::recir,l.c:: ;:nd mount-

i n g then1 in some mntlner a s to facilitat,e

t h e i r obsel.~,:~tioii Of t!?t ~ n ~ i ) t : $ ~nethocts

which t h e WI-iter h::s r~.'rtl the t e c h n i q ~ i c

described seems t o give t h r llr::? i.c.;:rlts

Specinlens :ire first i ' ~ ~ ! : t y t ~ t I 1 1 ~ - l ( s : i ~ : i i ~ , ~

them in a moist chan!?;cl- f o i ;: !v?i.iotl o f

12-24 hours T'erj- old ;!lid t 1 i i ~ s j i ~ ~ c , i ~ n < ; ~ s

may t a k e a s much ;I; 4 8 i10111.s 1 0 i.c,!:i\-

sufficiently to mailip~il:lte 17-ith s::i'r:ty, l > i i l

~isually it is sufficie~it to !C:I;-e ! l i c ~ ~ i i i i i?:.)

chamber o ~ e r night i-\ftc.r rel:isi*;g t l ~ i l

terminal segments of thp abtli*riicir :IL.I> re.-

moved and placecl i n a satur:itci! ~.)l~iticiil

a r e left i n t h e cold s o l u t i o ~ i f o r 12-2 1 l:o:~i.s

Overnight i s usually enough T h i s cie.~rs t!ic

s t r u c t u r e s suflicierltly without softeniiig o r

(listortirig them A f t e r t h i s clearing pl-ocexs

they a r e separated w i t h dissecting nccclies

under a microscope and cemented on :I e:i~-c!

point, on t h e pin w i t h t h e specimen

Detailed collection records a r e giveil olily

f o r t h e new species, while t h e general geo-

graphic tiistribution and seasonal c2ccul.-

I.ence a r e given f o r ;ill previui~?,ly desci,ibed

species T h e flower-visiting habit.: ;i!.;o a r e

given, a s f a r a s they a r e knux:n

T h e list of bibliogi~iphic references ~!!~rler

each genus and species incluites un1y thcjse

of some taxonomic, biologic o r ecologic sig-

nificance T h e reference t o t h e original dV2-

scription, i s almay:; included, :is :Ire t h e

veferences to most synonyms AI-ticies

\vhich mri-ely list t h e species a r e not in-

c.lrided

Iiees i i i ~ ? closcly related eco1ogic;~lly to t h e iiowerirrg pl:irits, anrl some knowledge of the details of t h i s relationship is essential

f o r n reasonably complete survey of bee s-;pecies f o r a n y pivi.11 area I n grnera!, t h e n:ltivc !!owering ;,lants will ha\-F: t h e more interesting 0 1 - 11nris11;il i11ac.i.t :i,<itors, a.:

i h c ~ t ' is more likclj l o he ;I closc c)cological

;issociwtioii between these iiative plarlts nnll

t h e 11:itive wild hrcs t h a t visit then? T l i con- lr.iist, il~t~'od!it.ed plnnt,s 21i.e nlo1.e likely to

!,rt ;-isitrtl 1)y the? rni!l.c3 gene~,alized species

of 1)i.e~ nhi:.h visit :I wide range of ?lost plants L i k e ~ ~ i s e , those introdticed be:: t h a t have s~:rvi;-cri a r e likely to be geilcl.a!ized forms t h a t visit a wide r a n g e of foorl p!unts

S u c ! ~ species a1.e nltich more likely to bc

~ q : t i p p e d f o r s~trvix-a1 ill the new eilr.iroli- ment thnn spccixlized f i ~ r m s th a t have :I

limited rnngc of host plants Ji:lil.:,- elf oiir 11;itire 11ees visit only one o r ;I limited 11i:ni- Ijer of cicwel; relaieci p1:int spacies : : c h 21s

a f e ~ v clasclj- i.el;ttcti ,ip:.:'ies fo1-mirig ;I

single genus In consequence, the)- a r c lirnit- c.tl in t h e i r dist:.il):ition t o t h e range ef t h e host p1:lnts X1::o sincc they a r c d c p e c d e r ~ t iipon thr: !lo\\-ers, they a r e lin~itecl seasoiial!> 11y ? h e I~!oorni!!g period of t h e plants Thus f!ight pcr,iclds : i ~ c a p t t o be I)l.ipf :11ir! pea-

!ri.apliic tli.sti.il)iition limited

The av;iil;~!)iliiy of nesting sites, ;11so, i s

;I l i ~ n i t i n g factor i n t h e c1istrih:rtion of bees,

; i r ~ i ? ,is a co1;seque;Ice such physiogi-aphic

f e n t ~ i r e s 21s character of t h e soil, d e g ~ e e and direction of slope, drainage, ;irno~lnt and clistribution of rainfall, etc have some bear-

i n g on t h e occurrence of bees On f:tvorable sites relatively dense populations may build

u p , especially i n those groups t h a t :Ire gregarious I t i s probably t r u e also t h a t many species r a n g e b u t a s h o r t distance:

f ~ o x t h e nesting ;!Yea T h u s t h e r e a r e mark- etl vrtriatioris i11 relative nburidance f r o ~ ~ i one locality t o another, ever1 though t h e host

p l a r ~ t s may he g e n e ~ a l l y availa1)lt

Climate of course is impr~rtarlt, limiting

;is i t does t h e geographic distribution of both t h e hort p l u i ~ t s and t h e bee visitors J3ut ~ v i t h i i ~ t h e geographic limits of t h i s distribution, t h e day-to-day o r hour-to-hour weather corlditions can be very limiting, so far a s a n y success in t h e collection of many species i s concerned Many bees cease ac- tivity in the absence o f snnshine, o r \trill

12 BEES OF THE EASTERN UNITED STATES, 1

remain inactive cs: iong as the weather i.: logical first abdominal segment is fused

Time of day is important, f o r with most

species activity is most marked thro1:gh

the middle four or fire hours of the day To

this, however, there a r e eyceptions as there

a r e a very few species t h a t a r e nocturnal,

crepuscular or matinal, or time their flight

to coincide with a bricf periocl early in the

clay when the host flowers a r e open, a s

shown by P j ~ r ~ , h o p c r ! : p z ~ s c n r - ~ l i ~ 1 1 ' 7 ~ ~ 7 [ ~

(Walt.) DC and its bee visitor, M p ? l ~ i h a -

l i c f z i s l l r s f l n n s Ckll

Thus i t can be seen t h a l to meet with

succew in the c?llecti?n of some of t'ne more

spcci,?li.;ecl b2es i t is llecessai\- to find a

combination of conditiolls t h a t inclucies tile

host p!tinC in bloom, adjacent to or in the

near ~ i c i n i t g of some f,~vor:tble nesting

site, ~ ~ i t l i i n the distribution limits of the

species, during the dai!y active period of

flight, and in i ~ a r m , c:llm, sunny weather

Generalized bees t h a t visit a wide range

of hurt plants tend to be in flight f o r much

!origer periods of time than the specialized

forms and a r e u;ually much more widely

and generally distributed It is these -forms

which a r e in flight through most of t h e

midsummer period, and i t seems lsossible

t h a t some of them have more than a single

gencrntion during a seilson The specialized

more restricted species tend to fly either

in the spring or in the fall and probably

hat e only a single generation

Morphology

With reg;ird to general structure, the

terminology nilopted by Alichcner (11744)

is followed, although without strict a d -

herence Some of the terms he has pro-

posed, x:hile certainly logical, a r e different

from those usecl f o r comparable parts in

other i~lsect orders, and their use is avoided

heye for t h a t reason So f a r a s possible

figures a r e used in place of, instead of as

supplements to, printed descriptions Only

where some additional explanation is de-

sirable is any space devoted to discussion

of the parts illustrated

The three body regic.2:~ a r e designated

the I ~ m r i , t1ln1.n.c and abdflnzen, in accord-

ance u i t h the terininologjr in the orders

other than the Hymenoptera Michener

(1944, p 167) uses t h e terms m e s o s o n z a

and mefaso??la f o r the thorax and abdomen,

since in all the Clistogastra the morpho-

1;,.opode7inz Thus the middle body region

i3:cludes four segments, rather t h a n t h e 11-ual three of other insects, and the abdo- men conversely includes only the segments 2-5 These terms, however, a r e limited in their application to t'ne ants, wasps, bees and related insects I t seems better t o em- ploy ? h e older and mere general!;; used ternlr in a work which i t is hoped n ill have general uyage I n numbering the al-dominal segments also the propodeurn will be dis- reg:~~-ded as representing the first, but in- .-.car1 the morphological segment 2, will be ct,n:yid~rect the basal one

-4 1::teral view of A ~ d , e n u (fig 1) and a Iront -,ri-,:: of the head (fiz 2 ) show t h e gencl-t:l ex-tci-nal charilcteristics Most of

t h e features illustrated a r e useful in f u r -

~ l i s h i ~ ~ g speci5c o r key characters in one

or another of the groups of bees, and an expl;.,nation of certain of them is desirnble The fovcaz (fig 2 ) a r e shallow depressed areas on the front of the head and a r e pres- ent in the females of the Andrenidae and most of the Colletidae They a r e poorly developed in the males of these two fami- lies and a r e lacking in all of t h e other groups

The sz~btctttcnnnl s u t z i r e s have some sig-

nificalice in classification but a r e m t h e r

~ ~ n s a t i ~ f a c t o r y as key characters a s they

a r e 50 frequently obscured by t h e dense pubescence of the face Only in t h e An-

d~enic!:\e a r e both the outer and inner pairs repi-ese~ltecl, the inner pair apparently being much or absent in all other groups Because of this they a r e rarely

u ~ e d in the keys or mentioned in the de-

- C riptiqns

The n ? ~ t e ? z , l u r ~ , a s in the higher groups of wasps, s1.e 1 2 - s ~ g m e n t e d in the females and 13-segmented in t h e males Usually sexual climorphism is so marked in t h e bees t h a t

t ! ~ i ~ ~ ~ ~ ~ is no problein in distinguishing the sex?., but where the similarity is col~sider- able, a s in some of the parasitic groups, this difference in t h e number of antenna1 segments is helpful The apical ten or eleven segments form the flagellum, and the relative lengths of these segments, es- pecially of the basal one, is of considerable value a s a key character

When, a s in some groups, the eye is closely approximate t o the base of t h e man- dible, there is no distinct malar space It

SECWD S ~ ~ ~ M A , R G I N A L CELL

I INTERCURITAL VEINS

; i

SUBMARGINAL CELL

PECL'RSENT VEIV

DISCO 5AL CELLS

is extenslbe 11-1 lilost of t h e social bee,, nb

\veil as in 2 few other unrelated solita~!:

species

The l a b ) u ~ i ~ .,nil ~ i ~ a l ~ d i b i e s a r e relatiiely

simple ge:leralized structures, not markedl)

different from those of more p r i m i t i l c

insects, 1,ut thev show a rather wide range

in form and in ] d a t i v e proportions The

remaining :ippendages forming t h e pro-

boscis, t h e ftzazillae and labizcnt, a r e espe-

cially significant in t h e recognition of t h e

families of bees; hence t h e importance of

having them pulled out into a visible posi-

tion while t h e insect i s still fresh artd

pliable I n the more primitive groups (e.g.,

Colieiidae) tl1ei.e is a ciose resemblance of thcsc slr~lcttires to t h x e in t h e wasps, with :: l.:~.:;adly truncate or bifX glossa, a 4- segni+nted labial paIpus and a 6-segmented

rilaxiliary palpus (see Colletes, in fig 3 )

1x1 tile st,ructurally more specialized bees

t h e y1os.x becomes acute aiid more or less elongated, the lacinia becomes reduced in size, t h e number of segments of t h e max- i!lary p:.~lpus fs reduced, and various other nlodifications may be found The labium and inaxillae a r e united basally by t h e V-

shaped submentam (lorum) which is at- tached on each side apically to t h e tip of

t h e cardo