104 SMER1NTHUS POPUL1. 



dicate the height at which the moth oviposits, but 

 more probably the height at which it was convenient 

 for me to gather leaves. 



The egg is of broad oval outline, nearly as deep as 

 wide, the shell glossy, but when magnified is seen to 

 be covered with very fine reticulation, irregularly vary- 

 ing from hexagonal to almost square meshes, in colour 

 pale yellowish-green. Some eggs I have measured 

 were over 2 mm. long and 1*75 mm. wide, but the 

 largest of both the layings mentioned above, those in 

 each case laid on the first day, were 1*95 mm. long and 

 1*6 mm. wide; those of the second, third, fourth, and 

 fifth days 1*8 mm. long and 1*6 mm. wide; those of 

 the sixth and eighth days slightly smaller ; those of 

 the ninth and tenth days 1*65 mm. long and 1*45 mm. 

 wide, and the last egg I found of the 1882 laying was 

 only 1*6 mm. by 1*4 mm. The empty shell is generally 

 eaten in great part by the young larva, though some- 

 times no more than the hole for exit ; every kind of 

 poplar seems acceptable in the way of food. 



My home-bred larvae burrowed for pupation an inch 

 or two into loose soil, but when digging I have found 

 the pupa barely hidden ; there seems to be scarcely 

 any silk spinning used. The pupa is extremely stout 

 in figure, cylindrical ; my measurements of its length 

 vary from 34 to 38 mm. ; the head piece slopes forward 

 very slightly, the wing-cases short, antenna- and leg- 

 cases not much developed, the abdomen going off in a 

 long curve to the tail, which ends in a rough scutcheon 

 with two knobs, and on the dorsal side a comparatively 

 small and somewhat flattened rough spike, set with a 

 short, stout, blunt spine ; the pupa skin roughly granu- 

 lated, the colour smoky-ochreous brown, with black- 

 brown clouding. (J. H., 27, 10, 86.) 



