14 TWENTY-THIRD REPORT ON THE STATE CABINET. [146] 



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 white, 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 five to nine, as appears in the following formula : 

 iA|4A ^ w. Ik _. The 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. The 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 walnut. 



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 immunity 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 months of June and July, two species of parasites were obtained 

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

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

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

 anterior and posterior legs, with the 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 26th of June and 3d of July. They 

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

 to be the Limneria fugitiva (Say), which Mr. C. states " seems also to 



* American Entomologist, 1868, vol. i, page 186. 



