36 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 



in time ; and since the Florissant beds must for a variety of reasons be 

 held to be the later of the two, the probability that they are Miocene 

 is aucrmented. 



•o' 



APOIDEA. 



TABLE OF SPECIES. 



Three submarginal cells 1 



Two submarginal cells 5 



1. Basal nervure strongly curved ; marginal cell ending in a point on costa ; 



insect small, about 6^^ mm. long, anterior wing somewhat over 4 mm. 



Halictus florissantellus. 

 Still smaller ; length about 4i mm., intense black 



Halictus scudderiellus. 



Basal nervure not, or not strongly, curved ; larger, anterior wing over 5 mm. 



long 2 



2. Second s. m. receiving first r. n. before the middle ; anterior wing about 



8 mm. long Calyptapis Jlorissautensis. 



Second s. m. receiving first r. n. beijond the middle, or at apex ; anterior wing 

 less than 7 mm. long 3 



3. Point of marginal cell a short distance from costa ; second r. n. bent near 



upper end ; first s. m. shorter than second or third on cubital nervure 



Lithandrena saxorum. 

 Point of marginal cell a short distance from costa ; second r. n. not bent near 



upper end ; size small Ceratina disrupta. 



Point of marginal cell on costa ; second r. n. not bent near upper end . . 4 



4. xVbdomen normal; second s. m. just three times as broad below as above 



Andrena sepulta. 



Abdomen clavate ; second s. m. narrower, not nearly three times as broad 



below as above Andrena (?) clavula. 



5. Stigma small ; insect broad and robust 6 



Stigma fairly or quite large ; insect smaller, or less robust 8 



6. Abdomen subglobose, without visible markings ; second r. n. passing well 



(about 120 M ) beyond apex of second s. m. ; breadth of marginal cell about 



630 n Dianthidiiim tertiarium. 



Abdomen longer, banded 7 



7. Wings strongly infuscated ; marginal cell about 720 fj, broad 



Anthidium scudderi. 

 "Wings clear ; marginal cell about 570 /i broad . . . . Anthidium exhumatum. 



8. T. m. with the lower end most apicad, so that it forms an angle with b. n. ; 



eyes prominent Lihelhdapis antiquorum. 



T. m. with the lower end most basad so that it is in line with lower end of b. n. 9 



9. Small, length slightly over 6 mm. ; abdomen dark brown ; width of marginal 



cell 255 fx Beriades halictinus. 



Larger, length 8 mm. or over ; width of marginal cell 300 ^ 10 



10. Abdomen light reddish brown ; head smaller Heriades laminarum. 



Abdomen banded ; head larger Heriades bowditchi. 



