264 MEMOIRS OF THE NATIONAL ACADEMY OF SCIENCES. 



Cocoon. — ^lore dense and perfect than usnal in other Notodontians; elliptical, hard, and 

 dense, flattened, the edges broad and thin, surface above well ronnded; closely resembling an 

 excrescence on the bark of trees. 



Pupa. — Body cylindrical, tapering at each end. '-Eyes prominent, a narrow earinated ridge 

 runs along the head from between the eyes to back of the place of origin of the anteiiu;Ti'' (Dyar). 

 End of the body rounded and obtuse; eremaster not prominent, and with no traces of a spine or 

 hooks, since the cocoon is so dense and i)erfect that the pupa can not fall out or be easily disturbed, 



" Pupation occurs in about two weeks after the completion of the cocoon, and the insects 

 remain in this stage throughout the winter." (Dyar, Psyche, v, p. 395.) 



Geographical distribution.— The species of this genus are to be found in the Old and New 

 ■worlds; but two occur in India, however, and the two Brazilian species are doubtfully referred 

 to Cerura by Walker. 



In North America it ranges throughout the entire continent north of Mexico, exchiding the 

 arctic region, including the cold temperate subregion and warm temperate subregion and the 

 humid provinces of the latter, and is represented by one species [cinerca, f Druce) in the Mexican 

 subprovince, and also in Guatemala. Its extreme northern and northwestern range is not yet 

 ■well known. Walker describes a form, perhaps V. occidentuUs, as a variety of C. bifida, from St.. 

 Martins Falls, Albany Eiver, Hudson Bay. 



SYNOPSIS OF THE SPECIES. 



A. Fore ■wings narrow, outer edge very obliqno; discal mark a black dot. 



Median black band very irregular on each side, rudely hour-glass shaped; extrabasilar line consisting 

 of four dots; no estradiscal lines C. hormiis 



Median black band broad, distinctly ,iud evenly edged on each side ■with black; extrabasilar line of 

 five dots; a distinct white broad scalloped extradiscal line ('. occideiitalis 



Median band usually narrow, much contracted or obsolete in the middle; three extradiscal scalloped 

 dark lines C. scoJoi)en(:Irina 



Like scolepcinli-'ma, but the baud and lines faded out; thorax all gray, and body and wings whitish gr.ay. 



C. ciiicrea 



B. Fore wings broad, outer edge inclined to be less oblique; discal m.ark a ringlet. 



Fort wings with no median d.ark band, but crossed by nine dark scalloped lines, the third and fourth 

 uniting to form a series of ringlets; hind wings often dusky; thorax white, with transverse black 

 lines C scilisciijita 



SYNOPSIS OE THE KNOWN LAllV.E. 



With longer cervical shield and shorter horns in Stage III than in the corresponding stage of horealis. 



C. occiclentalis- 

 Ditt'ers from multiscripta in that the dorsal reddish patch in the middle of the body does not descend so far 



down on the side C. horealis 



Difl'ers from C horealis .and occideiitalis in the less connected and narrower dorsal lilac red patches, and iu 



the end of the suranal jilate being sciuarer than that of C. occidentalis ('. vinerea 



Like horeaVis but paler, more jjurplish, and dorsal hum]) distinct C. scitiscripta 



Cerura borealis Boisduval. 



(PI. VI, figs. 10, 11, 12.) 



Dicraiioura borealis Boisd., Guerin. Icon. Regne Animal, t. 88, fig. 5, 1829, p. 519, 1844. 



Griffith's Cuvier's Animal Kingdom, XV, 1832. PI. XXXII, fig. 5, 5a, larva. (No description.)- 

 Centra borealis Morris, Syn. Lep. N. Amer., p. 238, 1862. 



Pack., Proc. Ent. Soc. Phil., iii, p. 375, 1864. 



Liutner, Rep. N. Y. State Museum, xxx, p. 196 (84), June, 1878. 



Grote, Xew Check List N. Amer. Moths, p. 20, 1882. 



Smith, List Lep. Bor. Amer., p. 31, 1891. 



Kirby, Syn. Cat. Lep.. i, p. 588, 1892. 



Neum. and Dyar, Trans. Amer. Ent. Soc, xxi, p. 189, 1894; Journ. N. Y. Ent. .Soc., ii, p. 114^ 

 Sept., 1894. 



