no. i. BOMBYCINE MOTHS OF NORTH AMERICA— PACKARD. 169 



on the outside by a rather large and conspicuous black spot; the midabdominal legs are green 

 or yellowish green ; thoracic legs black. 



On June 2 the larva had become 18 mm. in length, otherwise it did not differ from its 

 appearance directly after hatching. 



Mr. Joutel's figures illustrate the wide colorational differences exhibited in the same brood 

 of caterpillars. Some represent an entirely yellow individual, except the 11 turquoise 

 dorsal tubercles, and those of the infraspiracular row; and the black lateral line, which is wanting 

 in some of his specimens and mine. He found all variations between these and the very dark 

 larva. In the second stage of the larva the body and tubercles are black, with the exception 

 of the yellow dorsal portion of the second thoracic and abdominal segments 1-7, and the under 

 side of the bodj T , including the midabdominal legs. He tells me that other specimens have 

 as much black pigment on the body, but that the dorsal tubercles on the second and third 

 thoracic and eighth abdominal segments are as blue as in the light-colored caterpillars. 



The larva I had in Providence molted for the second time about June 4 or 5. 



Stage III : Length 20 mm. The head is now wholly pea-green. The two median pro- 

 thoracic, and the two dorsal tubercles on the third thoracic segment, and those of the lateral 

 row are turquoise-blue, but the two dorsal tubercles on the second thoracic segment are greenish. 

 The two third thoracic dorsal tubercles are thicker than those on the second thoracic segment, 

 and about twice as thick as those on the first abdominal segment. The medio-dorsal tubercle 

 on the eighth abdominal segment is much thicker than those near it. The proportionate size 

 of all the dorsal tubercles is as in the previous stage. Spiracles pale brown, not conspicuous. 



The black dots low down below the lateral ridge are now nearly obsolete. 



Anal legs with no external black spots, and entirely green. The thoracic legs green, with 

 a few black spots. 



Mr. Joutel, who had more larvae under inspection than? I, says, "All the larvae are gradually 

 losing the black pigment; the dark ones have only the base of the dorsal tubercles on the third 

 thoracic and eighth abdominal segments black, with the tips blue; also the lower half of the 

 face is black." 



It was found to have molted for the. third time June 23. 



Stage IV: Length 23 mm. (when underfed)-42 mm. The body is now thicker at the third 

 thoracic segment, and in fact somewhat so throughout, while the tubercles are smaller, and 

 all but those on the back of the third thoracic and eighth abdominal segments are decidedly 

 reduced in size. The slcin is now covered with minute rounded warts or granulations. The head 

 and body are pale greenish straw-yellow (more yellow than green). The tubercles are of the 

 same hue as in stage III. The six tubercles on the front edge of the first thoracic segment are 

 turquoise-blue. 



The two dorsal ones on the third thoracic segment are turquoise-blue. The medio-dorsal 

 one on the eighth abdominal segment, and the four on the side of the ninth segment are tur- 

 quoise-blue, but the two dorsal ones are yellowish, of the same hue as the skin. The lateral 

 series of tubercles are turquoise-blue, as before. On all the tubercles the setae are black, and 

 shorter than the tubercles themselves are high. 



The two dorsal tubercles on the front edge of the first or prothoracic segment are as large 

 as those on the second thoracic segment, while those on the third thoracic segment are nearly 

 twice as high as thick, also slightly smaller than in stage III. Each bears six black setae, and an 

 odd seventh bristle in the center. The setae are not quite so long as the tubercles are thick. 



The dorsal tubercles on abdominal segments 1-7 are now small, slender, scarcely half as 

 high as the two on the third thoracic segment, and evidently undergoing reduction ; each bears 

 three setae of unequal length, two of which are short, and one generally longer, though they 

 vary in length, the longest one being about as long as the tubercle is high. There are six setae 

 on the medio-dorsal tubercle of the eighth abdominal segment. 



Suranal plate with a rather stout turquoise-blue tubercle on each side near the middle, 

 each bearing seven short black setae; end of the plate armed with five small setiferous tubercles, 

 and an irregular row of black setae on the edge of the anal legs. 



