AMERICAN HYMENOPTERA. 1 i 1 



Xanthosmia gn. nov. (Type Osmia cordata Rob.) cordata. 

 G-nathosmia gn. nov. iType Osmia georgica Cresson) georgica. 

 Monilosmia gn. nov. (Type Osmia canadensis Cresson) canadensis. 

 Diceratosmia gn. uov. (Type Osmia quadridentata Cresson) quadridentata. 

 Leucosmia gn. nov. (Type Osmia albiventris Cresson) albiventris. 



TRYPETINI. 

 Andronicus cylindricus Cresson. 



ALCIDANEA Cresson. 



Females. 



Scutel swollen; head beneath smooth, shining, impunctate, edge of cheeks be- 

 neath with a row of long incurved hairs; clypeus with a median 

 raised line truncata. 



Scutel moderately convex ; head beneath punctate, long, pilose; clypeus without 

 a raised line producta. 



Males. 



Segment 7 broadly rounded ; ventral segment 2 longest, with a transverse sub- 

 apical ridge truncata. 



Segment 7 produced into a spine; ventral segment 2 with a great tooth-like pro- 

 cess producta. 



(^Prochelostoma gn. nov. (Type Heriades philadelphi Rob.) philadelphi. 



TRYPETES Schenck. 

 Females. 



Lower border of mandibles simple; clypeus einarginate, sides with two or three 

 denticles; maxillary palpi 3-jointed ; a little smaller carinatus. 



Lower border of mandibles sinuate at base, with subniedian dentiform angle: 

 apical margin of clypeus straight, with a distinct lateral tooth ; maxil- 

 lary palpi 4-jointed ; a little larger sp. nov. barbatus. 



Males. 



Ventral segment 2 subtruncate ; antenna longer, joint 3 about one-half as long as 

 4; flagellum testaceous; clypeus moderately bearded carinatus. 



Ventral segment 2 produced to a point ; antenna shorter, joint 3 more than one- 

 half as long as 4: flagellum blacker: clypeus strongly bearded. 



barbatus 



Ashmeadiella bucconis Say. 



2. MEGACHILI1SLE. 



MEGACHILINI. 



Chelostomoides rufimanus Rob. 



Oligotr opus gn. nov., campanulas sp. nov. i/ 



TRANS. AM. ENT. SOC"., XXIX. APRIL, 1903. 



