WHITE-MARKED TUSSOCK MOTH 
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each molt for several of the larvae as shown in the following 
table : 
Larva? 
No. 
1 
No. 
2 
No. 
3 
No. 
4 
Hatched 
May- 
3 
May 
3 
May 
3 
May 
3 
First Molt 
May 
9 
May 
9 
May 
9 
May 
9 
Second Molt 
May 
13 
May 
13 
May 
13 
May 
13 
Third Molt 
May 
18 
May 
18 
May 
19 
May 
19 
Fourth Molt 
May 
23 
May 
24 
May 
24 
May 
25 
Pupation 
May 
30 
June 
2 
June 
2 
June 
2 
Emergence 
June 
6 
June 
12 
June 
8 
June 
7 
Larva? 
No. 5 
No. 6 
No. 7 
No. 8 
Hatched 
May 3 
May 3 
May 17 
May 13 
First Molt 
May 9 
May 9 
May 25 
May 26 
Second Molt 
May 13 
May 13 
May 30 
May 30 
Third Molt 
Mav 19 
May 19 
June 5 
June 5 
Fourth Molt 
May 25 
May 26 
June 8 
June 12 
Pupation 
Emergence 
June 3 
June 9 
June 6 
June 13 
Lost 
Lost 
These rather few cases revealed the length of the larval period 
for the first brood to be 27 to 34 days and the pupal period to 
be from 5 to 10 days. These figures, of course, are for indoor 
conditions. 
On June 25 caterpillars of the second brood began hatching. 
The female which laid these eggs emerged June 12 and laid 
her eggs a few hours after emergence. 
It was observed from the larvae that matured that the males 
emerged a day or two before the females. The life of the adult 
female is very short and in this way mating was not delayed. 
Many experiments in the way of offering different food plants 
to the caterpillars and in changing the food from time to time 
were carried on. Eggs were collected during the winter from 
the following trees : birch, maple, elm, apple, and plum. 
In captivity it was found that the caterpillars fed readily on 
leaves of box elder, mulberry, catalpa, buckeye, horse chestnut, 
maple, birch, elm, lilac, apple, plum, cherry, pear, cottonwood and 
sycamore. They were found to eat the leaves of many herb- 
aceous plants as readily as those of trees. Leaves of dandelion, 
bluegrass, low-mallow, lamb’s quarter, clover, geranium, iris, lily 
of the valley, and plantain thus proved acceptable. The com- 
mon burdock was the only food which they refused. It was also 
found that they could readily be transferred from one food plant 
to another without serious consequences. 
Biology Department, 
Iowa Wesleyan College. 
