288 [Dkcemhkr 



iiiaining. Haviug tiuished its anoiuolous repast of" animal food, after a 

 brief rest, it betakes itself to its accustomed diet. 1 regret that the ex- 

 periment was not made, of depriving the larva of its egg-shell and skin, 

 with a view of determining whether they are essential to its health. 



Before the first molting, the larva measures from .4 to .45 in. in length ; 

 body cylindrical, with a whitish vascular line and lateral stripes, and faint 

 sub-dorsal lines; the thoracic horns barely visible; head smooth and uni- 

 colored. 



The tii'st molting was on the 16th and 17th. The head and caudal horn 

 are now granulated; thoracic horns prominent; the dorsal serrations, late- 

 ral stripes and thoracic lines distinct; the sub-dorsal lines (which are soon 

 to be effaced) still visible. 



Up to this period, fifty of the larva? had died, and a number had escap- 

 ed from their confinement, probably sufficient to have brought the mortal- 

 ity to forty per cent of the entire brood. T suspected that so large a loss 

 must have been owing to injuries sustained in their daily removal to fresh 

 leaves, although a delicate camels-hair pencil was emjtloyed, and the ut- 

 most care used in the operation. I learn, however, from Mr. Edwards, 

 that an equal mortality attended his brood of S. (jemiiiatus, which were 

 not handled, but permitted to make their way unaided to fresh twigs placed 

 beside them. This critical period safely passed, the few deaths which 

 subsequently occured, were clearly traceable to external injuries. 



Previous to the second molting, the larva measures from .6 to .7 in.; color 

 pale green, yellowish at the incisures; the dorsal serrations and lateral 

 stripes yellowish-green ; the thoracic and caudal horns pale yellow ; the 

 sub-dorsal lines have disappeared; the stigmata not visible, being of the 

 color of the body. 



The second molting commenced on the 22nd, on which day three larvae 

 molted, twelve on the 23rd, eight on the 24th, and the last on the 27th. 

 (The brood was now reduced to about a third of its original number.) 

 The dorsal serrations are now prominent, and the lateral stripes show gran- 

 iilations; caudal horn with brown granulations in front and rear; the stig- 

 mata appear, with a black central line. 



When ready for its third molting, the larva measures from I inch to 

 1.2 in.; head with whitish lateral lines; caudal horn a deeper yellow than 

 before; Icg^ tipped with brown. 



The third molting extended from the 2Sth of July to the 1st of Aug.. 

 Larva light green, with serrations and lateral granulations whitish; the 



