892 FIFTH REPORT OF THE ENTOMOLOGICAL COMMISSION. 



by a few, short, stout, black spines. The second is more rounded at the top, shining 

 black at the base, and resembling white glazed porcelain at the apex, with four 

 black spines. The next two are smaller, about 2^™™ apart on the front edge of the 

 segment, the lower of which is about 5^"^ from No. 2. These are very small and 

 black, the upper one having a trace of greenish white at the apex, and both are sur- 

 mounted with saveral short black spines. The lowest tubercles on segments 3 to 6, 

 inclusive, are small, with black bases, apices resembling white glazed porcelain, and 

 generally two black spines. The tubercles of the next row above, extending from 

 the third to the last segments, inclusive, are very similar in form and color, but 

 larger ; those of the row above this are slightly pear-shaped, a very little thickened 

 towards the outer end, of the same color as the preceding, and surmounted with from 

 four to six short stout black spines. Those of the next row on the third, fourth, and 

 fifth segments, and the corresponding ones on the opposite side of the dorsum — by far 

 the largest on the larva — are pear-shaped, largest outwardly, porcelain-white at the 

 base, with a band of shining black above, and a bright coral-red top, with from 

 six to eight stout black spines. The tubercles of this row on the sixth to the 

 eleventh segments, inclusive, are nearly as tall, but slimmer than those preceding, 

 slightly curving backward, porcelain white at the base, a very light straw color 

 above and armed with two black spines at the top. The dorsal tubercle of the 

 twelfth segment is very similar, but larger, and armed with several black spines. 

 The tubercle at the base of the anal proleg is smaller than those before it, of a light 

 bluish color, with black at the base outside. 



The most striking differences observed between P. Columbia and P. cecropia in a 

 brood of the latter raised by the side of the former are, first, the smaller size of 

 Columbia at each of the stages; the mature larva of Columbia is about 3 inches in 

 length, that of cecropia about 4. Secondly, Columbia is of a clear light pea-green 

 color, cecropia a dull bluish green, giving a much darker aspect to this larva. This 

 distinction of color is so marked that, if once observed, the one can never be mis- 

 taken for the other. Thirdly, Columbia has three pairs of coral-red tubercles, one 

 pair each on the third, fourth, and fifth segments ; cecropia has two pairs, one pair 

 each on the third and fourth segments. Then the color of these differ; those of 

 Columbia are a true coral or vermilion-red, while ail the cecropias 1 have seen have 

 these tubercles a color somewhat approximating that of resin. The remaining dorsal 

 pairs of tubercles to the twelfth segment and the central one on the twelfth are lemon- 

 yellow, while in colum,bia they are white at base and a very light straw color above. 

 The remaining tubercles of cecropia are black at the base, but with the look of white 

 glazed porcelain above. The distinctive characters show no tendency to run into 

 each other in any of the examples I have seen. As perhaps having a bearing upon 

 the question whether Columbia is a hybrid between cecropia and pi'omethea, I will say 

 that in six years of careful collecting at this place I have never taken a promethea, 

 nor has one ever been taken here to my knowledge, yet the empty cocoons of Colum- 

 bia have occasionally been found, mostly in larch trees, la one instance about 40 feet 

 from the ground. I am therefore convinced that Columbia is a good species, but 

 whether distinct from gloveri I am not prepared to express an opinion. 



4. The red tussock-moth. 

 Orgyia anti<iua {\^\\iu). 



This tussock caterpillar occurred frequently ou the larch at Bruns- 

 wick, in the early part to the middle of September. 



5. The white spotted tussock-moth. 

 Orgyia leticostigma (Abb. & Smith). 



We have found the caterpillar of this moth late in August in Maine 

 spinning its cocoon and preparing to transform into the chrysalis state. 



