MEMOIKS OF THE NATIONAL ACADEMY OF SCIENCES. 271' 



on the costa, a taint nan ow line, curved inwardly around to tbe first, cubital branch, curves inward 

 between tlie tirst and second cubital branches, outward below the third cubital venule, eiidin"' 

 in a black dot at the internal angle. A large, conspicuous, oblique, steel-blue black costal patch 

 extending inward and downward to the first cubital venule; a row of intervennlar marginal 

 black dots. 



Hind wings white, with a discal dot, and a dark spot on the iuuer angle. Fringe white, with 

 black dots. Beneath white, the dark patches and band showing through; the discal dot is- 

 distinct, especially on the hind wings, and there is a curved extradiscal narrow dusky line. Tarsi 

 black, ringed with white. 



In a type specimen from Plattsburg named by Mr. (i. H. Hudson (in United States National 

 Museum), another from Providence, li. I., which is more rubbed, the median baud is much broader, 

 scarcely contracted in the middle. 



In a series of six $ S from Colorado in the nuiseum of Brown University, presented by Mr. H. 

 L. Clark, one closely approaches G. cinerca in its white color and in having the black thorax nearly 

 overgrown with white hairs, while the median band on the fore wings is nearly obsolete, being 

 representeil only by a triangular costal dark spot and a small round spot near the inner edge of 

 the wing; in another specimen the band is very much contracted, only represented by a narrow 

 line on the cubital veni. On comparing such specimens it is seen that C. ciiierea may have 

 originated from this species, and that it is a more recent form than scolopemlrind. 



Larva. — Although the species is so widely diffused, its larva has not been detected except by 

 Mr. Thaxter in Maine, who says that it feeds on Populus, but gives no description of it. 



I copy, however, Dr. Dyar's description of the egg and different larval stages of what he thiidis 

 IS this species. 



The larva of Cerura acnlopendr'ma has not been describett, but I believe that I have observed it. No moths were 

 bred from the larvse here described; but several considerations render it probable tliat they are C scolopendrina sO' 

 that I venture to present my notes under thfi name. 



(1) C. scolopendrina is common throughout California and was talien by me in the Yosemite V.alley. 



(2) These larv;e have not been described before, and could only be C. paradoxa ' of the known Californian forms. 



(3) I am informed by Dr. Thaxter, who has bred it, that the larva of C. aqiiilonaris (:= scolopendrina) is much, 

 like that of C. cinerea, and those here described recall cinerca in the undulating outline of the dorsal patch. 



(4) Dr. Belir writes in answer to an inquiry: "[In the Larva of] Cerura scolopendrina the doTs:d band . 



is three times widened, or I would call it twice constricted, but the degree of the constriction is rather variable, so- 

 that sometimes, although rarely, the band is almost interrupted." 



E(/g. — .Slightly more than hemispherical, the base tlattened, smooth, sublustrous black, under a lens appearing 

 minutely punctured. Diameter, 1 mm. Under a half-inch objective it is seen to be covered with flat, irregularly 

 hexagonal and elongated reticulations which become very small at the micropyle. Between them the surface seems 

 smooth with a few extremely minute punctures. 



First larval stage. — Head round, slightly shining, dark red-brown, almost black ; cl3'peu8 and mouth parts paler, 

 ocelli black; a few short hairs; width, 0.5 mm. Body smooth, of even width; a pair of spinose subdorsal processes 

 on joint 2; the anal feet modified into spinose stemapods, 3 mm, long; cervical shield small, very dark. Color of 

 body blackish red-brown, feet and venter whitish; two greenish dorsal patches, one on joints 3-5, the other on joints 

 8-10; elliptical, diffuse at their ends; a third patch appears later, on joint 12. On the body are a nuraberof minute 

 setie. Tails twice annulatcd with yellowish and tipped with white. Extensile threads blai.^k, whitish at the base. 



The larviB eat only the parencliynia of the leaf during this stage. 



Second stage. — Head rounded, sliglitly narrowing to the vertex, its sutures deep ; color, even red-brown, with a 

 few minute yellow dots; width, 0.8 mm. .Joint 2 is swollen, its subdorsal processes conical, thicl<, spinose; low, 

 rounded, small, setiferous tubercles on the body, apparently normal in arrangement; anal plate and stenuipods 

 spinose. Body rust.v brown with two elliptical, diii'use, dorsal patches of yellowish green, the anterior one on 

 joints 2-6, the posterior on joints 8-10; subventral region and all tlie feet pale whitish. Tails red-brown at basal 

 half, then blackish, with two sordid white annul.ations. Lcugtli, 3.8 ram. As the stage advances the anterior patch 

 becomes larger, joins the subventral coloration, and is obscurely divided by a brown dorsal line, while the whole 

 dorsal region, except joint 11, becomes pale. 



Third stage. — Head higher than wide, roundly rectangular, flattened in front; reddish brown, the upper two- 

 thirds thickly covered with little round yellowish spots, but leaving a narrow line of the gi'ouud color on each side 

 of the central suture above the clypeus; autenme white; width, 1.15 mm. Body enlai-ged at joint 2, bearing a pair 

 of heavily spined subdorsal processes; tails minutely spined. The normal piliferous dots on the body consist of 



' There is good reason to believe that C. paradoxa is only a very pale form of C. einerea, the larva of which is. 

 well known. 



