2G8 MEMOIRS OF THE NATIONAL ACADEMY OF SCIENCES. 



setiferous flesby tubercles, which lie bt'tweeii tlie bases of the spiny anal legs or filaments, which 

 are about one-half or two-thirds as long as tlic body, an<l yellow, with two broad brown rings, and 

 brown at the tip. Body greenish yellow, marked as usual with lilac-brown, this tint mimicking 

 the dead, witliered brown of the edge of ])oplar leaves of late summer; it is a dark lilac-brown 

 with reddish biowii and lilac brown patches, and in this way the caterpillar mimics the dead 

 stained portion of tlie leaf on which it feeds and tluis escapes obseivation. From head to end of 

 mesothoracic segment a brown patch, succeeded by a pointed brown baud which extends to the 

 base of caudal appendages, but contracted on the eighth abdiiiiiinal segment, tlic dorsal tubercles 

 of which are yellow. 



Larva after lant molt. — Length, except caudal appendages, 17 mm. DifVers from foi-egoing 

 stage in the i)rothoracic si)iny horns being replaced by smooth, shining tubercles with faint traces 

 of the spines of the former stage; the sides of the thoracic segments more distinctly spotted, with 

 faint traces of broken yellow lines in the middle of the body. 



Cocoon. — "Like those of the other species of Cerura, l)ut rather flatter for its size. Length, 

 38 mm.; width, 11 nun.; height above the surface of the wood, (i mm." (Dyar.) 



Piq)a. — "Cylindrical, flattened a little on the ventral side, the ends rounded, uot tapering; 

 cases prominent, those covering the antenna' large; a slight depression behind thorax dorsally; no 

 crcnuister; color, red brown; cases finely wrinkled; dull; body smooth, slightly shiny. Length, 

 17 mm.; width, .Tmm." (Dyar.) 



Habits. — The caudal appendages are soft and extensible on their outer third, forming the 

 " flagellum," and are quickly jerked uj) when the ci^eature is disturbed; they are evidently delicate 

 repellant organs. 



The close resemblance in the lilac-brown patches of this caterpillar and others of the genus to 

 the sere and brown edges of certain of the leaves is remarkable, and ])lainly enough serves 

 to ])rotect the caterpillar from o1)servatioii. I have observed the same in other Notodontians, 

 especially Schi::ura iinicornin and allied forms. 



Food plant. — Species of wild cherry (Cerasns). In Edwards's Bibliographical Catalogue of 

 the described Transformations of North American Lepidoptera. page 70, the word "Salix," sliould 

 be replaced by "Cerasus," in line 13 from the bottom of the page. 



Geographical distribution. — Maine (Packard); Franconia, N. H. (Mrs. Slosson); Massachusetts 

 (Harris). Lintncr gives the following localities for C. borealis (emend.) : " New York, Pennsylvania, 

 Yirginia, Wasliington, D. C, Georgia, Missouri, August 2<i, at light (Kiley)." Plattsburg, N. Y. 

 (Hud.son); Illinois (Dyar); Ormond, Fla., darker than the one from Franconia, N. 11. (Mrs. Slosson);, 

 New York, Wisconsin, Carbondale and Champaign, 111. (French); Chicago, 111. (VVestcott). 



Cerura occidentalis Lintner. 



(I'l. VI, li-. 15.) 



Cerura borealis (in part. ;m(l cinerea) Harris, Rep. Iii.s. M.iss., p. SOfi, 1841; Treatise Iii.s. Inj. Vog., 3tl edit., 



]i. 4L'3, 1802. 

 Cerura occidentalis Lintner, Ent. Coutr., iv, p. 82, .Iniie, 1878. 



GrotK, New Chock List N. Amer. Motlis, p. 20, 1882. 

 8mitb, List L<>p. Bor. Amcr., p. 31, 1891. 

 Kirby, .Syn. Cat. Lep. Hot., i, p. 58S, 1892. 



Neum. and Dyar, Trans. Amer. Ent. Soc, xxi, p. 189, .June, 1891; .Jourii. X. Y. Ent. 

 Soc, li, p. 114, Sept., 1894. 



Larva. 



Freneli, Can. Ent., xiii, p. Ill, 1881. 



Packard, Filtb Ke)>. U. .S. Ent. Conim., \). .5()."), 1890 (description copied from Erench) (PI. XI, lis. 7, from 

 a colored drawing Iiy Dr. Lintner. This is more probably ciiierca or liorfalis.) 

 I'roc. Bost. Soc. Xat. Hist., xxiv. p. 554, 1890 (Stages II, III). 



Jifofh. — One i , and others examined. Very distinct from C. borealis and seolnpendriiui. Head 

 and collar duslcy wliite; a black band crosses tlic^ thorax between the fore wings, bcliind wliich 

 are yellow scales; black over the .scutum. Fore wings ashy white, outer edge and base sordid 



