114 MEMOIRS NATIONAL ACADEMY OF SCIENCES. vol. xn, 



(revised nomenclature) being united (stalked) for some distance beyond the cell. The vena- 

 tional differences between the two genera or subgenera may be expressed as follows: 



Fore wing with III 2 well developed; hind wing with III and IV separating beyond the cell, either at a point with IV 2 

 or farther on Coloradia. 



Fore wing with III 2 absent; hind wing with III and IV separating before the end of cell, the upper corner of which is 

 not angular Eudyaria. 



However, Dr. Dyar, having a good series of Coloradia (C. loiperda), finds that veins III and 

 IV of hind wing are very variable, ranging from connate to long-stalked.] 



COLORADIA VENATA (Butler). 



Plate XX, figs. 7; LIV, figs. 7, 8. 



[Dirphia venata Butler, Proc. Zool. Soc. London, 1871, p. 83.] 



Eudyaria venata Grote. [It is the type of Eudyaria Grote, Mittheil. Roemer Mus., No. 6.] 



Imago. — One o* , one ? . A larger stouter species than the North American one. Body 

 with a thicker, denser vestiture than in C. pandora. Uniformly Vandyke brown; the wings 

 with no bands; but the veins are covered with dark brown scales and are very distinct. The 

 wings, especially those of the hinder pair, are darker along the outer edge. The discal spot is 

 small, obscure, a little paler than the surrounding part of the wing. The hind wings are a little 

 larger and sienna brown or tawny in o" , in 9 black; discal spot not visible beneath. There are 

 no roseate scales in this species. 



Expanse of the fore wings, 6" 94 mm.; 9 100 mm. 

 Length of a fore wing, 6" 46 mm. ; 9 50 mm. 

 Breadth of a fore whig, <s 24 mm.; 9 26 mm. 

 Length of a hind wing, 6* 36 mm. ; 9 39 mm. 

 Breadth of a hind wing, <? 25 mm. ; 9 25 mm. 



This species differs from our American species by its much larger size, the stouter body, 

 the absence of lines, and the dark veins contrasting with the lighter brown ground color of the 

 wings. It is an example of the tendency in South American representations of this genus and 

 Meroleuca to have dark thickly scaled veins contrasting with the less densely scaled surface of the 

 wings ground, rendering the color lighter, or with a tendency to translucence, a tendency carried 

 out to an extreme in the tropical and subtropical genera Heliconisa and Pseudaphelia. I have 

 compared my specimens with the examples so named in the British Museum. 



Geographical distribution. — This species inhabits Buenos Ayres. 



Larva.- — Last stage: Length 90 mm.; width of head 8 mm. Head yellowish brown, 

 smooth, and shining. Body cylindrical, as usual dark brown. The tuft-like spinulate tubercles 

 are much slighter and slenderer than in Automeris viridescens, the spinules being long and very 

 slender, cylindrical, and they ascend, not spreading out much; they are somewhat reduced as in 

 Coloradia. 



The pro thoracic and other dorsal tufts as in A. viridescens, but slighter and slenderer. 

 There are about the same number of spinules on each spine: 15 on the dorsal pro thoracic seg- 

 ment, 20 on the dorsal second thoracic segment, 16 to 20 on the dorsal third thoracic segment, 

 20 on the dorsal first abdominal segment, 24 (12 on each side) of the median spine on eighth 

 abdominal segment. The tip of each spinule is acuminate, dark. The suranal plate is just 

 as in that of A. viridescens. The legs, both thoracic and abdominal, are all dark. 



Pupa. — 9 , 6* of nearly same shape as in that of Automeris viridescens, but the surface 

 smooth, not granulated or rugose; cremaster conical, simple, without hairs; that of 9 rather 

 larger and stouter than 9 of A. viridescens. Length <? 40 mm.; thickness 15 mm.; 9 40 mm., 

 thickness 17 mm. 



Buenos Ayres (Amer. Museum of Natural History, New York). 



