THAEGELLA.— MNASITHEUS. 565 



primaries are comparatively short and broad, blunt at the tip, with the costa strongly 

 arched from the base to the apex, and the outer margin slightly rounded ; the cell is 

 less than two-thirds the length of the costa; the discocellulars are oblique, the npper 

 one longer than the lower, the latter twice the length of the third median segment, 

 which is exceedingly short ; the lower radial is distinctly depressed at the base ; the 

 first branch arises a little beyond the middle of the median nervure, the second close 

 to the lower angle of the cell. The secondaries are rounded at the anal angle ; the 

 discocellulars are long and faint, the lower one oblique, the upper one transverse. 

 The body is moderately stout, the head large. The middle tibiae are without spines, 

 and the hind tibiae have two pairs of spurs. There are no secondary sexual characters 

 visible on the primaries of the male (Tab. C. fig. 24), but the secondaries have a fringe 

 of long hairs along the inner edge of the abdominal fold in this sex. 



1. Thargella Miginosa, sp. n. (Tab. c. figg. 24, 25, <s .) 



Alia nigro-fuscis, unicoloribus : subtus rufo-fuscis, anticis ad angulum analem late pallid ioribus ; palpis aureis. 

 5 ignota. 



Hab. Nicaeagua, Chontales (Janson). — Colombia, Cacagualito {H. H. Smith, in Mus. 

 Pittsburg); British Guiana; Amazons, Santarem. 



We have seen four males of this species : three worn examples in our own collection 

 and one, from Colombia, in perfect condition, belonging to the Pittsburg Museum. 

 The genitalia of two of them have been dissected, and they agree perfectly. Our figures 

 are taken from the Chontales specimen, the genitalia being shown on Tab. C. fig. 25. 



MNASITHEUS, gen. nov. 



The two species we place under this generic name are both of very small size, and of 

 an almost uniform fuscous colour above and beneath, with the cilia paler. We take 

 M. cephis as the type, this having an inconspicuous treble brand on the primaries of 

 the male; the second species is Pamphila simplicissima, H.-S. ( = Cobalus ?iigritulus i 

 Mab.): the iirst-mentioned insect is only known to us at present from Mexico and 

 Guatemala ; the other is a widely distributed and common Tropical-American form. 

 The genitalia of the males of the two species are very similar. 



The antenna? are a little more than half the length of the costa, and have an elongate 

 club, terminating in a long crook. The third joint of the palpi is short and conical 

 (longer in M. simplicissimus). The primaries are somewhat pointed at the tip, and 

 have the costa slightly arched at the base; the cell is much less than two-thirds the 

 length of the costa; the discocellulars are oblique, the upper one about twice the 

 length of the lower, the latter slightly longer than the third median segment ; the 

 lower radial is depressed at the base; the first branch arises from the middle of the 

 median nervure, the second from close to the lower angle of the cell. The body is 



biol. centr.-amee., Rhopal., Vol. II., December 1900. 4 d 



