295 



spiracle between two blue tubercles, which are armed with three or four 

 black spinose hairs. Tenth segment like the others, except tbat it has no 

 feet. Eleventh with one nearly spherical or ovoid, yellow tubercle on the 

 top, with eight black spines upon it; a spiracle each side between two blue, 

 spinose tubercles. Twelfth segment with four blue, spinose tubercles, paler 

 at the summit, and deeper blue at base; nearer the tail two small, terminal, 

 blue tubercles with a few short spines on them. Cushions of the last pair 

 of feet at the tail, blue. 



Some of these larva were found on the wild cherry tree, Aug. 3, 1825. 

 These caterpillars often fail of producing moths in consequence of being 

 destroyed in the pupa state by parasitic or intestine enemies. I once found 

 eighteen larvae of some parasite (apparently the same that infests the grape 

 vine sphinges) in the posterior half of the larva of B. Cecropia, which had 

 spun its cocoon, but had not strength to transform to a pupa, and the cocoon 

 had only its external thick coat. In these cocoons are sometimes found the 

 cocoons of an Ichneumon, which devours the larva of the Bombyx and oblit- 

 erates all traces of it, leaving in its stead a firm ovate cocoon for itself. 

 This, when the Ichneumon comes out, is opened at the top by a little lid 

 becoming detached, as in many flies. 



Saturnia lo Fabr.' 



Lives on the Balm of Gilead tree; the caterpillar also eats clover and 

 elm leaves. When young gregarious, feeding and moving like the pro- 

 ccssionary' caterpillars, in files. Larva green, spinous, spines poisonous. 

 Measures two and a half inches. In transforming, enclosed itself in a case 

 of leaves lined thinly with silk. 



Larva seen. Moulted. Spun cocoon. Imago. 



July 17. July 27, Aug. 3, 11, 23. 



" 10. " 1C. 



July 7, 1849. Just hatched, or only a few days old, on Robinia viscosa, 

 in a cluster beneath one of the leaves; yellowish rust color, with black, 

 branched spines. Head pale brown, polished. Saw them Avalking in file 

 when a week old. About July 10 they moulted, ate up their cast skins, and 

 appeared of a paler, reddish brown color, with black spines. July 22, 

 moulted again, ate their skins, and then were of a greenish color, with a 



