140 TWEXTY-THIED PiEFOET OX THE StATE CaBIXET. 



lateral row, the substigmatal and the ventral (the latter interrupted on 

 the proleg-bearing and penultimate segments) are twice the length of 

 the superior spines, of a glossy black color, with a tapering trunk, which 

 gives off laterally and apically about twelve cylindrical branches of 

 nearly equal length with the trunk ; of these branches the lateral ones 

 are M'hite, translucent and mucronate, having the terminal spinule, 

 black, slender, acute and of about one-half the length of the branch 

 from which it proceeds. The number of spines borne by the several 

 segments is from live to nine, as appears in the following formula : 

 ]^,4£>, (sT^ K), n^ u.^ rpi^g stigmata are of the color of the abdominal 

 spots, and acutely ellipsoidal in outline. The caudal plates and shield 

 are deep red, with pitted surfaces and short hairs. The legs are glossy 

 black, with black hairs. The prolegs are red, of the shade of the head, 

 with black hairs exteriorly, granulated interiorly, a smooth glossy spot 

 externally, and with fuscous terminal booklets. Beneath, a median 

 line of round red spots, of which there is one on the middle of each 

 segment from five to eleven. 



Food-plants. — l^\\e larva probably feeds on most, if not all, of our 

 oaks. My colony, during its progress to maturity, partook of five 

 species and was readily changed from one to another. Mr. Walsh 

 states'" that "the eggs of the moth are deposited, out west, on the 

 scrub willow and different species of oak ;" from which it may be 

 inferred that the former (unknown to us under its local name) is the 

 plant on which it more frequently occurs in that region. It has also 

 been reported to Mr. "Walsh as occurring on the wild cherry and on 

 black T/alnut. 



Parasites. — Although so enveloped in spines as scarcely to leave a 

 space sufficiently exposed for other than a random thrust of an oviposi- 

 tor, our larva does not enjoy entire innmniity from parasitic attack. 

 Of a colony of about thirty individuals found after their second molt, 

 eight of the number proved to have been ichneumonized, and during 

 the niduths of June and July, two species of parasites were obtained 

 from them. Several days after the larvie were collected, two of them, 

 which had meanwhile increased very little in size, and had rested fre- 

 quently from feeding, were found apparently atfixed to a stem by their 

 anterior and posterior legs, with tlie central portion of the body raised 

 up and enfolding in its curve, a parasitic cocoon lying between it and 

 the stem and closely clasped on each side by the prolegs. The cocoons 

 disclosed their imagines on the 2Gth of June and 8d of July. Tliey 

 were submitted to Mr. E, T. Cresson for determination and Avere found 

 to be the Limner ia fug itiva (Say), which INIr. V. states '"seems also to 



* American Entomologist, 18C8, vol. i, page 186. 



