no. i. BOMBYCINE MOTHS OF NORTH AMERICA— PACKARD. 173 



minutely barbed, the barbs being short. The two dorsal tubercles on the eighth abdominal 

 segment are no higher than those in front, all being of uniform height. There are hairs on the 

 supraspiracular tubercles. 



At the end of this stage (Apr. 16-17) the larvae became 8-12 mm. in length, though the 

 head is no larger than at first. 



The body is livid brown-black, but paler on the imder side, almost glaucous-green, with 

 a yellowish tinge, so that the lateral or pleural fleshy ridge becomes a faint greenish-yellow line. 

 The tubercles are jet-black, and the hairs black, with gray ones intermixed. 



Other examples before molting have a pale dull whitish band extending across the labral 

 region of the head, and a lateral row of livid pale whitish spots. 



Stage II: Molted April 16-17. Length of body 11-12 mm., width of head 1 mm., about 

 twice as great as before. Directly after molting the head, legs, and tubercles are all white. 

 The lateral broken line or series of pale greenish-yellow lateral linear spots is much more distinct 

 than before, being now conspicuous, while the body is dull livid blackish. Now there are 

 scattered over the body long white hairs, and similar ones form the central one or two setae, in each 

 tubercle; they are about one-third as long as the whole body, but in the lateral or infraspiracular 

 row of tubercles all the radiating hairs are long and whitish. The white hairs are most abundant 

 on the prothoracic plate and head. The short hairs on the body are still black. Under side 

 of the body livid. 



Stage III: Molted the second time May 1. Length 24 mm.; head larger, width 2.5 mm. 



The most decided change is in the prothoracic hairs and those on the sides of the body, 

 which are straw-yellow, while the anal legs are edged with straw-yellow. The longest dorsal 

 hairs are about a quarter to a third as long as the entire body. The body is still rather long 

 and slender, and much more hairy than in the larva of Antheraea. The tubercles are still more 

 prominent, black, the ends and the tuberculets livid. The hairs are long, not stiff, but a little 

 crinkled, and they partially conceal the tubercles. The latter are still all of the same size. 



Stage IV: Third molt occurred May 17-20. 



Length of body 22 mm. ; width of head 3 mm. 



There is now a decided change in coloration and markings. The head is nearly as wide 

 as the body, black, the clypeus-anterior white; lab rum yellowish; the head armed with long 

 uneven yellow hairs. 



The body is still only moderately thick, and is long and slender, not at all like Antheraea 

 in shape; the segments are not convex, but flat, and of the same thickness to the end of the body, 

 but the anal legs arc large and triangular. 



The tubercles are larger and more prominent than before, and very conspicuous, as they 

 are white or yellowish white. The prothoracic plate bears long hairs, and on this segment there 

 are no decided dorsal tubercles, the vestiges being low and flattened, while the lateral ones are 

 fairly prominent and black. 



The second and third dorsal thoracic tubercles are no larger than the abdominal ones; 

 those of the third thoracic segment a little larger, however, than those on the second thoracic 

 segment; and those on the sixth abdominal segment a little larger than those on the seventh 

 and eighth segments (one on the sixth is larger than its mate). 



The two dorsal tubercles on the eighth abdominal segment are separate, like the others, 

 and show no signs of coalescence; they are slightly larger than those on the ninth segment, 

 which are also separate. 



Each dorsal tubercle gives rise to about four radiating stout, sharp, slightly dusky sets, 

 while from the center rises a very long yellow hair, or more often two or three, usually three 

 such hairs; the skin between the tubercles bears on the top and sides of the body long fine white 

 hairs. The longest yellow hairs are about one-third longer than the body is thick. The area 

 around the base of the tubercles is white, due to crowded flattened snow-white warts, which 

 are crowded around the base of the tubercles and scatterred between so that the dorsal region 

 is white, though interrupted; the sides of the body are black, inclosing the dull livid spiracles. 



