Lejpidojpterological Contributions. 361 



Habitat. — Mexico (Mirador). 



A beautiful species, the ornamentation and coloration of the 

 primaries recalling that of the very different Oeratomia amyn- 

 tor Hubner sp. (C. quadricornis, Harris), a resemblance which 

 has suggested the specific name. 



Family TIIYPJDAE. 



Plattthykis, n. g. 



Antennae, rather long, slender, filiform, naked. Head, sunken, 

 'improminent, impressed on the prothorax ; palpi large, obliquely 

 ascending, held free from the front ; eyes, globose, small ; vertex, 

 narrow ; the supra-caputal squamation is rough ; epicranium, con- 

 cealed. Prothorax, wide, square in front and short, not projected 

 in front of the insertion of the wings as in Thyris. Thorax sub- 

 quadrate, densely and closely scaled ; abdomen, stout, of equal 

 width, not constricted basally, as long as, but hardly exceeding the 

 secondaries ; anal segment constricted. Wings, wide ; primaries 

 more than half as wide as long; apices obtusely rounded ; external 

 margin entire, slightly sinuate, being outwardly rounded before 

 internal angle ; internal margin straight, equalling the costal mar- 

 gin in length, the external margin being hardly oblique. Second — 

 aries, wide and full, nearly as large as the primaries, external margin 

 very sinuate. Legs, stout, thickly fringed with strong hair. 



This coarsely scaled genus with broad wings, differs from 

 Thyris in the entirety of its corporal structure, so as to render 

 any neurational comparisons unnecessary to support its vali- 

 dity. Compared with Thyris, the thoracic parts are less com- 

 pact and much less advanced before the insertion of the wings, 

 giving the insect a noctuid appearance, which its strictly fili- 

 form, rather long and slender antennae, full, short abdomen, 

 and wide secondaries tend to exaggerate. The opposed cha- 

 racters give to Thyris its strongest resemblance to the Aege- 

 rians. Thyris vitrina, Boisd., Mon. Zyg. 6, 19, pi. 1, fig. 5, 

 belongs to this genus. 



