136 



MEMOIRS or THE NATIONAL ACADEMY OF SCIENCES. 



Hahil.t.—])r. Harris, iii his "Treatise," quite fully describes the liabits of tliis tcntiuliabiting 

 caterpillar, remarking: '' When young they sometimes fold up one side of a leaf for a nest, and 

 eat the other half He also fully describes the tent made by the social mature larva-, which wo 

 have also observed on the poplar, " nuide of a single leaf folded or curled at the sides, and lined 

 ■with a thin web of silk." He also states that ''the catcrjiillars go out to h cd ujion the leaves 

 near to their nests." It thus ai)pears that from early larval life the caterpillars live in much the 

 same way as the fully grown larva>, dwelling in tents, and, unlike most Notodontians, continuing 

 to live socially in "swarms of twenty or more," until tliey tlisperse. preparatory to ])ni)ation. 

 While feeding exposed, they are jjrobably not eaten by birds, as their colors and markings serve 

 as "danger signals." 



The following account is copied from Harris's Corresjiondeiice (p. 210). He observed them on 

 the r>alm of ( Ulead: 



August ami SepU'inlier, 1835: Gregarious catciiiillnrs on the BmIim of (lilcnd trc(^; foldiuf; ii|i tlic IciilaiKl lining 

 it with sill;; as a romiiioii web. the i)etiole beiug also I'asteneil to tlic tnmk l)y silk. 



l.aria. — Color of tlie larva yellow; head, gcniiiiate ttihercles on the f'onrtli and eleventh segments, ti]i of last 

 segment, and trne feet, hlaek; three narrow dorsal and tlueo hroader lateral vitta>, and spiracles, black. The larva 

 is much like that of Closlera unacliurela (Krnst, Ki'i, tig. 214) and ('. recliisa (F.rnst, 1U5, (ig. 216) and closely resembles 



('. aimitomosii. Thin cocoon formed in ,a box October 4, 183."). Another cocoon 

 formed in October, 18.37, disclosed the imago June 15, 18.38. 



August 10, 1838: Found the larvie in great abundance on the Balm of 

 Gilead tree. These caterpillars are gregarious, and form a common shelter 

 consisting of a leaf folded longitudinally and lined with a thick web of silk, 

 beneath which the insects are sheltered when uot feeding. They cat tlie whole 

 of the leaves except the veins, which remain untouclied. The petioles of the 

 small leaves used as habitations are fastened with silk. The larger leaves sub- 

 sequently used for shelter are not thus secured. Tlicy do not eat the leaves 

 which serve for hal)itations, but sometimes fold one-balf of the leaf anil eat the 

 corresponding side. When fully grown the caterjiillar measures lA inches or 

 more in length. They do uot vary in color or markings at difl'erent ages. Body 

 slightly hairy, light yellow; the head, true feet, a, ilonlile wart on the fourtlt, 

 another on the eleventh anal valve, three slender dorsal stripes and three broader 

 lateral ones on a dusky ground, and the spiracles, bbu'k. In the oldest caterpil- 

 lars there is an orange-colored line at the sides of the body below the spiracles. 

 The upper lateral black stripe is the broadest and becomes indistinct toward the 

 second, which gives to the sides the appearance of .a broad, dusky stripe marked 

 with three black lines. Tlio thinly scattered hairs on the body are whitish, and 

 proceed indiscriminately from the surface, and not from regular tubercles. 



The caterpillar of this moth occurred on the poplar (B. grandl- 

 (lentata), at Providence, Septend)er 11 to 15. They were living 

 within a tent ma<lt' by drawing two or three leaves together, .several 

 smaller branches of the tree having been defoliated by them. It ]iuiiatcd a few days after, the 

 moth ajipeariug in the breeding cage June 1 of the iie.\t year. 



The eggs occur in April and May and July and August: the larva- from May to July and 

 August to September; adults. March, April, and May, and .Inly and August (ai.so ;ill winter months 

 in confinement in breeding cages. (Riley.) 



Food plants. — Different si)ecies of i)oi)lar, especially /'. /rfHiM?oiV7c&. 7. y;«//« was reared by 

 Professor French on the willow, po])lar, willow maple.) (Kiley.) 



Gcinjidpliicul ili.slribiiiioH. — It ranges fiiim IMaine and Canada to (ieorgia (Abbot) and 

 Florida (Packard), thus extending tlu(iM.i;h the Ai)iiiilachian and Austroriparian snb])rovinces.^ 

 Maine (Packard); Massachusetts (Harris, Sanborn. Slinrtlefl) ; Amherst, Ma.ss. (Mrs. Kern;ild); 

 lihode Islaiul (Packard); New York (H.Edwards, Elliot, Dyar); Kacine, Wis. ; Chicago, HI. 

 (Westcott); southern Illinois (French); Georgia (Abbot); Jacksonville, Fla. (i'ackard); Indian 

 River, Florida (H. Edwards); Te.\as (Hiley); Denver, Colo., Ai)ril ;5(), May!) ((lillette). Its western 

 and soiithwestern limits are not exactly known. Professor Frencli .sends me tlie following 

 localities of si>ecimens in his collection: /. inclxsa, Maine, New Vork, Pennsylvania, \N'isconsin, 

 Ohio; var. invcrsa, Canada, Lincoln, Nebr. ; Colorado; var. pulla, normal, Carbondale, 111.; 

 Lincoln, Nebr. 



Flfi. 62.— Hfjid oi' ]iup.l of h'hthyitra 

 hicliua. 



