N... 1434. VENEZUELAN SYXTOMII) MOTIlS^KLAdES. 545 



Expan se. — 24 mm . 



Hahitat. — Suapure, Venezuela, 



Types. — Cat. No. 8422, U.8.N.M., and in collection of the author. 



The partial nakedness of the constricted dorsal segments seems to 

 be a natural character which might easily escape notice or be attributed 

 to accidental denudation, and likel,y does not occur outside of this 

 genus, in which it seems limited to a few or possibly, though not 

 likely, two species. 



ARGYRCEIDES SUAPURENSIS, new species. 



3fale. — Head and body brown-black; palpi in front, edge, and some- 

 times lower part of frons, and spots fore and aft on basal joint of 

 antenna?. brownish white; lines behind eyes white; vertex with some 

 grayish hair; teguhe and patagia with grayish or yellowish edges; 

 shoulders and thorax with some grayish or yellowish hair; pectus 

 with whitish patches; fore coxa? below, and patches on middle and 

 hind coxje whitish; hind tibiw fringed with rough hair on outer half 

 of inner edge; abdomen with the back part of second dorsal segment, 

 and the front half or two-thirds of third dorsal segment naked (the 

 exposed skin brownish 3'ellow); the third dorsal segment with or with- 

 out (in types with) yellow on edge; the next four dorsal segments 

 edged with yellow, but very narrowly on seventh segment; the third 

 segment ventrally whitisli V)ehind. and the next four ventral segments 

 with narrow 3'ellow or whitish fringes; wings yellow hyaline, the 

 veins brown-black with some yellowish splashes, and the margins very 

 narrowly brown-])lack. Hind wing with the lobe on inner margin 

 clothed with black hair. 



Fetnale. — The whitish patches on fore coxte are absent. 



Expanse. — 23-26 mm. 



Hahitat. — Suapure, Venezuela. 



T(/pes.— Cat. No. 8423, U.S.N.M., and in collection of the author. 



The partial nakedness of the constricted dorsal segments in this 

 species is a constant and natural character discovered from a critical 

 examination of quite a number of specimens, nearl}' all of which are 

 in excellent condition. The underside of the third segment is nor- 

 mally more or less bared in front, the deiuidation most likely i)eing 

 caused bv some action of the legs. 



This species constitutes a new generic section on account of the hind 

 tibiie being fringed. 



DIPTILON HALTERATA Fabricius. 



Hahitat. — Suapure, Venezuela. 



It is strange that this species, whose hind wings are of little if 

 an}'^ use in its flight, should be taken so far north of its tirst-known 

 habitat. 



