Entomol o QIC a l Contrib utions. 141 



similar to the " nettle-rash.'' As would naturally be expected from 

 the comparative size of the larva^, the sting is not so severe as that 

 of Heinileuca Maia (Drnry), or Ilyperchiria lo (Fahr.)"^ 



A critical examination of the larva, by a partial removal of its 

 hairs, revealed the existence of clusters of short, slender, acute, white 

 bristles, directed upward from the several tubercles of the lateral and 

 subdorsal rows, the presence of which had previously been unnoticed, 

 under their covering of the long hairs surrounding and effectually 

 concealing them. Upon touching the bristles with the hand, they 

 were found to be the source of the sting experienced. 



Fifth molt — ^The fifth molting through which the larvae were 

 observed to pass, and their subsequent changes, were not recorded, 

 xldditional collections of larvae made at Center were thoughtlessly 

 added to the colony, which, with other circumstances, prevented the 

 completion of their history. Of the above collections, one of the 

 number spun its cocoon on the 29th of August, attached to the 

 bottom edge of the bell-jar confining it. 



An alcoholic matured specimen in my possession, which had 

 attained more than ordinary size, measui'es one inch and three-tenths 

 in length, by one-third of an inch broad. Its head, drawn within the 

 first segment is black, as are also the tips of four or five of the ante- 

 rior stigmatal papillae. 



A larva taken at New Baltimore, N. Y., feeding on plum leaves, and 

 brought to me August 31st, was more elongate than usual ; its three 

 anterior segments were clothed with hairs of a brownish shade, and 

 the hairs of its posterior extremity were prolonged so as to form a 

 short tail. It made its cocoon September 1st, but did not develop 

 the imago. 



Cocoon. — The cocoon is of a tawny-brown color, oval in form, often 

 tnodified by the surface to which it may be attached, and occasionally 

 contracted near its apical end ; its average size, taken from fifteen 

 specimens, is three-fourths of an inch in length, by one-third of an 

 inch in diameter. It is of a firm, parchment-like texture, capable of 

 sustaining considerable pressure from the edge of the nail before 

 yielding to it. Its exterior is irregularly covered with a thin web of 

 rather coarse threads, in which, under the microscope, a few of the 

 plumose hairs of the caterpillar may be observed ; underneath 

 this, the outer coating of the cocoon is thinly extended over its apical 

 end, to the extent of about one-tenth of an inch. Upon stripping 



* Twenty-third Report on the N. T. State Cabinet, 1872, p. 



