STYLOPIDAE. 277 



Tribe III.— 9IYODITINI. 



Oral organs perfect ; labrum not visible ; eyes not emarginate, 

 very finely granulated ; antenna? inserted on the front, inside of 

 the eyes, on a line with their anterior margin, flabellate in both 

 sexes, but with the tenth and eleventh joints connate in the fe- 

 males ; scutellum not covered by the prothorax ; lateral suture of 

 prothorax entirely wanting ; elytra very small, wings not folded ; 

 middle coxae very widely separated ; epimera of metathorax 

 large, episterna wide ; ventral segments five, with the genital 

 sheath of both sexes prominent. 



One genus, Myodites, is contained in this tribe ; it is repre- 

 sented by several species from the Atlantic States ; they are found 

 on the flowers of Solidago in August. 



Tribe IV— RHIPIDIINI. 



Oral organs atrophied ; eyes very large, finely granulated, 

 occupying the greater part of the head ; antennas (of the males) 

 contiguous, flabellate ; prothorax without any trace of lateral 

 suture ; scutellum not covered by prothorax; elytra short, pointed^ 

 dehiscent ; wings not folded ; middle coxa? not widely separated ; 

 ventral segments eight. 



Female without elytra and wings ; larviform. 



No species of Rhipidius has yet been found in the United 

 States ; but as Blaita germanica, in which JR. blattarum is 

 parasitic, has been introduced, it is proper that the attention of 

 observers should be directed to the discovery of its parasite. 



Fam. lxil— s tylopidae. 



Oral organs atrophied, except tlie mandibles and one pair 

 of palpi. 



Head large, transverse, vertical, prolonged at the sides, 

 forming a stout peduncle, at the end of which are situated 

 the eyes, which are convex, and very coarsely granulated. 



Antennas inserted on the front, at the base of the lateral 

 processes of the head ; forked in our genera. 



Prothorax exceedingly short. 



Mesothorax short, bearing at each side a slender, coria- 

 ceous, club-shaped appendage, with the inner margin mem- 

 branous ; this appendage represents the elytra. 



