Studies on Life-history of Bomhycine Moths. bl 



are deposited. The shell is ornamented with a longitudinal series 

 of parallel fine delicate ribs, between which are cross ribs, parallel 

 and very near together; on the upper (micropylar?) end of the Qg,^ 

 are faintly marked, rude, slightly raised polygonal cells, and at the 

 extreme end is a group of more raised smaller areas. Color yellow. 



It will be interesting to examine the freshly hatched larva, and I 

 should be greatly obliged for a lot of fertilized eggs. 



Young larva. — Length 9 mm. It is now of the same general 

 shape and colors as the full-grown worm. The head is dark chest- 

 nut, as is the now well-developed prothoracic shield. The shape and 

 pale color of the end of the body are as in the fully-grown worm. 



The case is at this time very irregular, much more so than that 

 of the fully-grown larva ; it is lined yvith silk, with which the 

 "frass" or casting are somewhat intermixed. 



The case of the worm in the last stage is about an inch and a 

 quarter long, and half an inch wide; it is flattened cylindrical, and 

 formed of two leaves properly trimmed and sewed together; the 

 midrib of each half extending along near the middle of each surface. 

 Each end of the case is closed after preparation by an orbicular flat 

 silken lid, fastened all around. 



Full-fed larva. — Length 30 to 38 mm., when retracted about 15 

 or 20 mm. The head is large, about as wide as the prothoracic 

 segment: somewhat flattened in front on the face, which forms a 

 declivity adapted to form a stopper to the opening of its sack ; the 

 cuticle is dense black, deeply rugose and corrugated, especially on 

 each side of the clypeus ; the region of the vertex is rough and 

 coarsely punctured, but without the irregular furrows of the ante- 

 rior region or face. The mouth-parts are all black ; the mandibles 

 unusually thick and strong, and rounded on the cutting edge. The 

 antennae are very extensile, long, thick, and well developed. But 

 this larva is especially remarkable for new structures not known to 

 exist in any other caterpillars, viz., a pair of long appendages, the 

 use of which is quite unknown. They arise by a slender stalk 

 behind and a little above the eyes, on each side of the head ; the 

 base is cylindrical, but the appendage soon becomes flattened or 

 compressed, and flattened bulbous at the end. The structures are 

 brittle, not flexible, and they easily break off; they are about as 

 long as the head. 



The ])rothoracic segment is dorsally black-brown, solid, chitinous, 

 thick, smooth and shininir, forming an unusually solid shield, which 



