698 CONNECTICUT GEOL. AND NAT. HIST. SURVEY. [Bull. 



APOIDEA* 



To this superfamily belong insects like the honey-bee, the 

 habits of which are quite diverse, as can be seen by a perusal of 

 the remarks under the family headings in the following pages. 



Key to Families. 



1. Females and most males with a flat triangular area on 



apical dorsal abdominal segment 2 



Females and most males without a flat triangular area on 



apical dorsal abdominal segment 10 



2. Clypeus hardly protuberant, and mandibles not commonly 



beveled; labrum concealed except at base, and provided 

 with a basal process or raised area; posterior angle of man- 

 dible not in front of posterior margin of eye; metathorax 

 produced beyond postscutel, in profile at least strongly 

 convex, usually with a posterior and a dorsal space; tongue 

 acute, flat, rarely filiform; labial palpi with first joint vary- 

 ing in size and shape but with second, third, and fourth 



joints simple 3 



Clypeus protuberant, or mandibles beveled so as to show all 

 of labrum or a great portion of it; labrum large, without 

 a basal process; posterior angle of mandible before pos- 

 terior line of eye; thorax in profile declining beyond scutel; 

 postscutel on posterior face of thorax, metathorax at 

 most a little convex; tongue filiform; first and second 

 joints of labial palpi flat 7 



3. Labrum not free from mandibles and not as large as clypeus 4 

 Labrum free from mandibles and as large as clypeus 



DUFOUREID/E p. 720 



4. Hind metatarsus invariably narrower than tibia 5 



Hind tibia and metatarsus of equal breadth 



MACROPID/E p. 720 



5. Marginal cell acute toward front edge of wing 6 



Marginal cell truncate toward front edge of wing 



panurgid;e p. 721 



6. Basal vein forming more or less perfectly an arc of a circle; 



face with no pubescent depressions or fovese 



HALICTID^ p. 699 



*The classification here adopted is a modification of Charles Robertson's admirable 

 classification of the bees of Carlinville, Illinois. 



