86 Studies on Life-history of Bombycine Moths. 



Stage III. — Length 10 mm. Molted August 30th to Septem- 

 ber 1st. The characters of stage IV are now indicated. The head, 

 however, is still shining entirely jet-black, and is rather narrower 

 than the body. The body is black, with a subdorsal stripe at first 

 white and afterwards becoming yellow as the larva becomes older 

 and larger; also an infraspiracular lateral wavy white longitudinal 

 stripe, the latter the most sharp and distinct, and containing on 

 each segment a black piliferous wart. 



From the tubercles on the 2d thoracic segment long white and 

 black hairs overarch the head ; similar tubercles and hairs, but 

 shorter, arise from the Sd thoracic segment. The dorsal tubercles 

 are black, arranged in a trapezoid, and from each arises a verticil 

 of 15-16 straw-yellow hairs varying in length. The verticils on 

 the sides of the body are black, with shorter white ones intermixed. 



On the first abdominal segment are two twin dorsal black j)encih 

 appearing as if one; they stand up straight, and are about as long 

 as the body is thick. There are none on the succeeding segments 

 until the 8th, which bears a black pencil not quite so thick as the 

 anterior one, and more irregular, and directed backward. The 

 thoracic and abdominal legs are black, the plantse pale. 



Stage IV. — Molted September 5th, and described the next morn- 

 ing. Length, directly after molting, 10 mm., afterwards reaching 

 a length of 15 mm. Just after exuviation and when 10 mm. long, 

 the row of seven median dorsal double arched black tufts have 

 appeared, these being undeveloped in the previous stage. The 

 body also is thicker, though at first little longer, and the verticils 

 of hairs are longer, and the hairs themselves much more numerous 

 and dense, so that the body and subdorsal stripes cannot be seen 

 through them, though it can easily be in the third stage. The long 

 dorsal hairs in front and at the end of the body are black; those on 

 each side of the seven black median tufts straw-yellow, while the 

 ground-color of the sides of the body, and the hairs low down, are 

 black. The head is black. The lateral or infraspiracular line is 

 now white. A part of the overarching prothoracic hairs are white. 

 All the legs are dark, the abdominal ones livid at the end and on 

 the plantae. 



Not having carefully observed and noted all the transformations 

 of an individual larva, I had supposed that there were only five 

 stages, but while writing out these notes, one larva brought with 

 me from Maine to Providence, and which was in the stage just 



