116 INSECTS INJURIOUS TO FOREST AND SHADE TREES. 
destroying vast groves; three annual broods; the larva peculiar from emitting from 
‘ the tips of its tuberculous spines a pun- 
Ifo] off larva skin; the beetle usually black 
Wada 7 on the prothorax, with the sides yellow 
sy b zs and the wing-covers yellowish, with three 
ter Riley. It may be destroyed by syringing the trees 
with a wet preparation of London purple or Paris green. (Riley, Amer. Ent. iii, 159.) 
gent milky fluid; transforming on the leaf, 
Fic. 53.—Streaked cottonwood beetle: a, beetle, interrupted lines of black or bluish spots. 
di] i 
Hh ; 
the pupa remaining in the partially cast- 
normal form; b, ¢, d, e, showing variations.—Af- 
Hl ) )} i a) 
: mn ai ) 
I = 
| 
dh 
| he: 
t | AW ihe & 
pets 2g 
\ JAS) Ce 
SAWS me VAR aI i e 
= UG ay \) § ral A aa 
a My a A 
i bai Wi 
ahi 
: zi 
% 
y 
Fig. 54.—Grub of streaked cottonwood beetle: a. eggs; 6, one enlarged; c, newly 
hatched larve; d, d.d, larvw of different ages; e, pupa, nat. size; f. one of the 
middle segments of the body of larvaseen from above, showing tubercles, enlarged. 
Atter Riley. 
&. THE COTTONWOOD DAGGER-MOTH. 
Acronycta populi Riley (lepusculina Guen, ?) 
Devouring the foliage and not unfrequently stripping the tree, a caterpillar which 
rests curled around on the leaf, and is easily recognized by its body being covered 
with long, soft, bright-yellow hairs, and along pencil of black hairs on top of segments 
4,6,7, 8, and 11. (Riley.) 
This caterpillar is sometimes 
destructive to the foliage of the 
cottonwood in Missouri. There 
are two broods of these worms 
ach year; the first brood ap- 
pearing in June and producing 
moths by the last of July, the second brood appearing the last of Au- 
