1893.] 14.0 [Packard. 



spines tapering to the end, which is slightly forked and setiferous, and the 

 spines are minutely spinulated ; the two horns are about two-thirds as long 

 as the body is broad. They are represented on the third thoracic segment 

 by two minute conical black tubercles, the homologous ones on the ab- 

 dominal segments being minute and greenish, tipped with black. Those 

 on the sides of each segment are larger, acutely conical and black. On 

 the eighth abdominal segment are four conical black tubercles, two dorsal 

 and two subdorsal, one on each side. On the ninth segment is a single 

 median conical tubercle, not quite so high as those on the eighth segment, 

 but larger at the base. Tlie subdorsal tubercles on this segment are 

 slightly larger than those on the eighth segment. The suranal plate is 

 subcordate, being excavated in front ; behind it is subtriangular, with two 

 black tubercles at the end, which are smaller than tlioseon the side in front 

 of the middle ; the suranal plate is greenish, like the prothoracic segment, 

 while the body is tinged with yellowish, with eight faint rather broad 

 whitish longitudinal stripes. The spiracles are black. The thoracic legs 

 are black. The anal legs are greenish, with a blackish patch on the out- 

 side near the planta. 



In this and the next stage it continues to feed on the under side of the 

 leaf. 



Stage 7F(?).— (After third molt, June 29 ) Length, 8 mm. The head 

 is still black, but the two horns are now wholly black, as long as the body 

 is thick, and spinulated. All the other spines are solid and black ; the two 

 dorsal spines on the eighth abdominal segment being two or three times 

 larger than the others. The body is now somewhat reddish above as well as 

 beneath, and the longitudinal stripes are reddish. The prothoracic spines 

 are now rudimentary and button-like. 



Stage V (?). — (After fourth molt, July 5, Bridgham.) Length, 

 10 mm. The head is now gamboge yellow, smooth and polished. The two 

 horns as before, being rather slender and spinulated throughout. The 

 body is yellowish green, with faint darker green longitudinal stripes. 

 The tubercles are obsolete, except those on the eighth and ninth abdominal 

 segments, which are black and moderately large. 



The following notes were made on caterpillars found in Maine and rep- 

 resent the two last stages of the larva. 



Stage F(?). — Length, 20 mm. Head cherry red, about two-thirds as 

 wide as the body, smooth and rounded. Prothoracic tubercles arranged as 

 in the previous stage, but a little larger and more conspicuous ; in one ex- 

 ample the anterior and posterior dorsal ones are coalesced. The second 

 thoracic horns are black, not much more than half as long as the body is 

 broad. Ifow the white stripes alternate with the dark-green ones, which are 

 quite distinct, the black tubercles being situated partly on them. The 

 tubercles on the abdomen are longer and sharper than before, and on the base 

 in the middle of the suranal plate is a transverse black plate. The black 

 plate on the ends of the abdominal legs are larger and more conspicuous 

 than before. 



PROC. AMER. PHILOS. SOC. XXXI. 14L S. PRINTED MAY 18, 1893. 



