7<> WM. H. ASHMKAI). 



12. Hind tibial spur in 9 normal; abdomen subdepressed, thinly fasciate with 



wliite hairs; "J, with the second ventral segment simple, not produced 



into a spine 13. 



Hind tibial spur in 9 broad, sulcate beneath ; body hlack. the abdomen .sub- 

 glabrous, distinctly punctate and usually subfasciate, the ventral 

 scopa rufous; clypeus at apex simple, the disk sometimes with a 

 smooth impression ; mandibles 3-dentate; anterior tibial hook wanting 

 or indistinct ; 'J, with the second ventral segment armed with a long 

 spine or tooth. 

 % pygidium elongate-quadrate, the apex slightly rounded, not emarginate 



or forked Acaiithosmia Thorns. 



^ pygidium trapezoidal and deeply emarginate at apex, therefore bidentate, 

 the sixth dorsal segment laterally slightly sinuate, but entire at apex, 

 ah hough on its disk apically is a slight median furrow or sulcus. 



Acaiithosmioidcs Ashm. 1.. g. (Type 0. odontogaster Ckll.). 



13. Body black, not at all metallic ; pygidium in ^ not tridentate 14. 



Body metallic ; pygidium in % tridentate. 



Clypeus in 9 subemarginate or truncate, in % tridentate; thorax above 

 clothed with dense fulvous hairs; abdomen fasciate, the ventral scopa 

 rufous, rarely whitish: mandibles in 9 3-dentate, in % bi-dentate; 

 pygidium in % deeply bi-emarginate, forming teeth, the median 

 tooth acute, the lateral teeth rounded at apex, the sixth dorsal seg- 

 ment laterally sometimes dentate Trideiitosmia Schmiedek. 



11. Clypeus at apex serrate-crenulate: anterior tibial book distinct ; front wings 

 with the transverse median nervure uniting with the menian vein a 

 little before the origin of the basal nervure or interstitial ; mandibles 

 in 9 3-dentate, in % 2-dentate; % with the pygidium semi-circular, 

 entire, the sixth dorsal abdominal segment laterally strongly emargin- 

 ate, forming a tooth. 



iloplitis Klug = Ctenosmia Thorns. (Type 0. adunca Panz.) 



Clypeus anteriorly rounded, unarmed ; anterior tibial hook generally wanting 

 or poorly developed, obtuse ; front wings with the transverse median 

 nervure uniting with the median vein a little beyond the origin of the 

 basal nervure; mandibles in both sexes 3-dentate; % with the pygi- 

 dium emarginate at apex or forked, the sixth dorsal abdominal seg- 

 ment laterally sinuate, dentate. 



V ill liocopa Latreille = Furcosmia Schmiedek. 



Clypeus at apex unarmed; body black, with fulvous hairs, the abdomen 

 fasciate, the scopa rufous: mandibles 4-dentate; % with the pygidium 

 with a deep impression or fovea on its disk, the sixth dorsal abdominal 

 segment laterally dentate, the middle femora armed with a tooth 

 beneath Megalosinia Schmiedek. 



Subfamily II. Megachilin^e. 



tThe Leaf-cutting Bees). 



The bees placed in this subfamily closely resemble those in the 

 former, ami it requires long practice and an experienced eye to 

 separate some of them from each other, although the head, as a rule, 



