LEPIDOPTERA. 239 



p. 380), the latter of which we have also seen. "A specimen of 

 Papilio Asterias is in my collection, and was captured by Mr. 

 J. Meyer of Brooklyn, L. I., two or three years since. It is a 

 fine instance of a perfect hermaphrodite. The right wings are 

 both male, the left wings both female, distinctly marked upon 

 both surfaces with no suffusion of color. The size is that of 

 the largest specimens of Asterias. The Saturnia Promethea 

 is in the collection of Mrs. Bridgham of New York, and is a 

 curious instance of an imperfect hermaphrodite. The left an- 

 tenna and left primary are male ; the right antenna and left 

 secondary are female ; the right primary is also female, but the 

 right secondary is something between the two, neither male 

 nor female. The color of the upper surface is nearly the same 

 as the under surface of the male. On the under side the 

 color and markings of the left primary are male, but the other 

 three wings are female. The color and markings of the male 

 Promethea are quite diflFerent from those of the female, and on 

 this hermaphrodite the confusion of the sexes is conspicuous. 

 It is a bred specimen. The body had been viscerated, so that it 

 is impossible to determine its sex." 



The larva of Ctenucha, which resembles that of Arctia, con- 

 structs its cocoon out of the hairs of its body, without spinning 

 any silken threads, so far as we could ascertain by microscopi- 

 cal examination. The hairs of this, as of probably most hairy 

 caterpillars, but more especially the Bombycid larvae, are 

 thickly armed with minute spinules, so that by being simply 

 placed next to each other, they readily adhere together. The 

 cocoon is finished in about twelve hours. We once noticed 

 a Ctenucha larva just beginning its cocoon. Earl}^ in the 

 morning it described an ellipse upon the side of the glass jar in 

 which it was confined, out of hairs plucked from just behind its 

 head. From this elliptical line as a liase, it had by eight o'clock 

 built up, rather unequally, the walls of its cocoon, in some 

 places a third of the distance up, by simply piling upon each 

 other the spinulated hairs, which adhered firmly together. At 

 four o'clock in the afternoon, the arch was completed, and the 

 larva walled in by a light partition, and soon afterwards the thin 

 floor was made. No silk is spun 'throughout the whole opera- 

 tion, while in the cocoon of Pyrrharctia Isabella there is a 

 slight frame-work of silk upon which the hairs are placed. 



