THE CANADIAN ENTOMOLOGIST. 183 



After Third Moult. — Length 12 hours after the moult, tV to tth* inch; 

 scarcely different as to color and spines from previous stage ; black, the 

 lower part and under side olive-green ; the white hairs over surface give a 

 hoary appearance to all the black area ; the tubercles on head still more 

 numerous, varying in size, more decidedly cone-shaped, the one on vertex 

 largest. Duration of this stage less than two days. 



After Fourth Moult. — At 12 hours, tV inch. Two days later full 

 grown. 



MATURE LARVA. — Length A inch ; slender, of nearly even thick- 

 ness from 2 to 1 1 ; the upper surface black, thickly dotted with fine yel- 

 low-white points or tuberculations, larger and smaller (some of the smaller 

 white), the former placed on the cross-ridges of the segments, the others 

 irregularly scattered on and between the ridges ; each of these gives out 

 a white hair ; under side yellow-green ; a black stripe passes between the 

 pro-legs ; 2, 3, 4 are black, and 5, 6, 11 to 13 have much black ; in line 

 with lower lateral spines a bright yellow line or stripe in long crenations, 

 one of which extends the breadth of the segment, and another similar 

 line is above spiracles, the two curves meeting at the spines ; under these 

 is a russet space making a pretty wide band, not evenly colored, and 

 varying in individuals ; a fulvous patch, always small, often a mere dot, 

 above and back of each spiracle ; occasionally the upper yellow line is 

 reduced to a patch on each segment, and sometimes this is enlarged and 

 conspicuous ; spiracles sub-oval, yellow rings with black centres ; feet 

 black, pro-legs green ; on 2 is a dorsal collar bearing several small white 

 spinose processes, and many white hairs, which are bent forward ; the 

 spines are in seven rows, one dorsal, three on either side, being upper, 

 middle and lower lateral ; the dorsals run from 5 to 12, the first laterals 

 from 3 to 12, the middle from 3 to 13, the lower from 5 to 12 ; the lower 

 laterals are greenish-yellow, with bristles of same color, the 5 upper rows 

 are black, from blue-black bases ; all these spines are slender, tapering to 

 point, with a white bristle at tip, and a few short black ones about the 

 sides ; along base are bunches of small green irregular tubercles, with 

 hairs ; head sub-cordate, black, shining, with many conical tubercles, large 

 and small, mostly white but some black, the one on vertex a little larger 

 than others, each with its hair ; these hairs are black on upper part of 

 face, white on lower. The black changes to dark brown as the larva pro- 

 gresses, and the russet band loses its distinctive color, becoming olive- 

 green. Duration of this stage about four days. 



