86 



E. T. CRESSOX. 



the anterior tarsi of tlie females more or less ciliated with spines; in 

 the subgenus J^riocncmis the intermediate and posterior tibiae are ser- 

 rated exteriorly, and the anterior tarsi are simple; \fhi\e m Agenin 

 all the legs are simple; tarsal claws sometimes toothed beneath near 

 the base, sometimes cleft. 



Abdomen exceedingly variable in form, being generally ovate or ob- 

 long-ovate in the females, and elongate and sub-depressed in the males; 

 in some species the form is long, narrow, and more or less cylindrical, 

 sometimes sub-clavate, sometimes ovate and depressed above, and vary- 

 ing from sessile to petiolate. 



The species of this genus are numerous, and are most of them easily 

 separated; but in the black species of the subgenus Pnmpllus there 

 seems to be a great similarity, and it is difficult to separate them, un- 

 less the specific characters are well marked. 



Subgenus POMPILUS. 

 This subgenus is characterized by the anterior tarsi of the females 

 being more or less ciliated with spines, and by the intermediate and 

 posterior tibiji3 being more or less spinose, without being serrated exte- 

 riorly as in the next subgenus. The shape of the posterior margin of 

 Figure .3. the prothorax seems to be a 



good specific distinctive cha- 

 racter, as is also the shape of 

 the anterior margin of the 

 'clypeus, which, however, 

 generally differs in the male 

 and female of the same spe- 

 cies. In some species the 

 form of the cells of the wings 

 is very constant, while in 

 others it is exceedingly vari- 

 able ; the same may be said 

 of the armature of the legs. 

 The accompanying outline fi- 

 gure is given to illustrate 

 some of the characters of the species belonging to this .subgenus. Spe- 

 cies Nos. 23, 50, 51 and 52, because of the different structure of the 

 head, prothorax and front legs, do not, strictly speaking, belong to 

 this subgenus, and may belong to Farapompilus Smith, (=i¥<x-ro;>- 

 tc.ryx St. Farg.), but until the characters of that genus are better de- 

 fined, they arc, provisionally, included under this head. 



