142 



FOURTH ANNUAL REPORT OF 



disturbed, it curls itself up, and then the sutures of the joints are seen to be 

 r<?ddish brown, in strong contrast with the black of the rest of the body. If 

 carefully observed, th% spines will be seen to be barbed, as represented at h. 

 This worm feeds, mostly during the night, upon the wild Sun-flower 

 (Hdianthus decapetalus), the different species of Plantain (Plantago), and 

 upon "Willows. My friend J. A. Lintner, of Albany, N. Y., thinks it like- 

 wise feeds on Black Locust, as he has often found it beneath that tree and 

 has fed it on the leaves. It comes to its growth in the fall, and curls up 

 and passes the winter in any shelter that it can find, being especially fond 

 of getting under the bark of old trees. In the spring, it feeds for a few 

 days on almost any green thing that presents itself, and then forms a loose 

 cocoon, casts its prickly skin, and becomes a chrysalis. The chrysalis is 

 black, and covered with a beautiful pruinescence, which rubs off almost as 

 readil}^ as that covering a Duane's Early plum. It has a flattened blunt 

 projection at the extremit}-, armed with a few barbs and bristles. 



In a few exceptional instances I have known both this and the follow- 

 ing species to go through all the transformations and produce the niotb in 

 the fell. The chrysalis state lasts but about a fortnight when the moth es- 

 capes. 



The accompa- 

 nying illustration 

 (Fig. 64) represents 

 the ffemale moth at 



a, and the male at- 



b. The upper por- 

 tion of the abdomen 

 is steel-blue, or 

 blue-black, marked 

 1 o n g i t u d i n a 1 1 }' 

 along the middle 

 and sides with yel- 

 low or orange. 

 With this excep- 

 tion, the whole in- 

 sect is white mark- 

 ed and patterned 

 with dark brown, 

 as in the figures. 



The male differs from the female principally in his smaller size and more 

 acuminate wings, and by the narrower abdomen, which is also generally 

 duller in color, with the pale markings less distinct. The markings on the 

 wings, vary in a striking manner in difterent individuals, the oval or ellip- 

 tical rings sometimes filling up, especially in the male, so as to look like 

 black blots. This insect is considered rare in New England, but is much 

 more common in the Mississippi A^alley. It occurrs still more abundantly 

 in the Southern swamps, where the larva is dubbed " Fever Worm" by the 

 negroes, under the absurd impression that it is the cause of fever and ague. 



