99 



which closed its cocoon in the early part of September, appeared on 

 the 27th of April. The larva is said to be frequent ; the male is rare 

 and flies with great swiftness. Seldom more than one larva is found 

 on a plant ! How is this to be accounted for ? All the trees on which 

 I found larvae of Thyridopteryx, had a great quantity of new and old 

 cocoons. Those cocoons which I obtained from off the Ambrosiae in 

 East Florida were mostly solitary ; possibly these were Abbot's insect. 

 The cocoons were slightly different, but only from the difference be- 

 tween the stalks of the Ambrosia and the young shoots of Cupressus 

 intermixed with the silk. I did not pay attention to the opening, as 

 they all seemed closed up finally. 



And now it remains for me to speak of a third insect from the United 

 States, which in the larva state makes a house for itself, but which 

 seems to belong to a different group of the Lepidoptera. 



Of this moth I possess but one specimen, taken in July, 1838, at the 

 Warm Springs, in the lovely valley of the French Broad river, on the 

 western frontier of North Carolina. For the details which follow I am 

 indebted to Dr. Harris, who communicated them to me in a letter 

 bearing date Sept. 26th, 1840. 



After some remarks on other Lepidoptera, he says — 



" Do you recollect the moth you sent me for examination, numbered 

 266, and respecting which are these remarks in your manuscript ? — 

 * 266 I took in July, at the Warm Springs ; it seems allied to Dryo- 

 campa, but distinct : it will come under no English genus.' Your spe- 

 cimen is a female ; we have a much larger one, a male, in our Society's 

 collection, and Dr. Melsheimer has recently sent me a pair, with the 

 cocoon. The annexed sketch may recal the insect to your recollec- 

 tion ; it is fi'om the largest specimen. 



"Light reddish ash-colour or 

 pale fawn,| finely sprinkled all 

 over with minute black dots, 

 with a larger blackish dot on 

 each fore wing, and a narrow 

 dusky band across both wings 

 angulated near the margin of 

 the fore wings. Antennae bipectinated to the tip in both sexes, but 

 much wider in the male, and suddenly tapering and bent towards the 

 tip. Palpi very small, maxillae obsolete. 



" In its form and falcated fore wings it resembles Bombyx Mori, but 

 the neuration is somewhat different, and the wings do not seem to be 

 reversed in repose, that is, the fi-ont edge of the hind wings does not 



H 2 



