282 
Psyche 
[December 
turbed. These observations were in corn and certain other host 
plants in which the insect occurs abundantly. The observations 
were also confined to that section of New England where the 
insect occurred in large numbers, an area bounded by Marble- 
head, Mass., on the north, Arlington, Mass, on the west and 
Quincy, Mass, on the south. The results of these observations 
are shown in Table I. 
For all these localities and in all host plants the average 
winter mortality was 9.4 per cent, being highest in pigweed 
{Amaranthus retroflexus L.) and least in Cocklebur, (Xanthium 
sp.) and Smartweed {Polygonum sp.). 
TABLE No. 2. 
Winter Mortality Found in the Spring of 1923 in Various 
Host Plants. 
Host Plant 
Num- 
ber of 
Col- 
lec- 
tions 
Num- 
ber of 
locali- 
ties 
Total 
num- 
ber 
of 
larvae 
Num- 
ber 
larvae 
dead 
Mean 
per 
cent 
larvae 
dead 
Highest 
per cent 
dead-in 
any col- 
lection 
Lowest 
per cent 
dead, in 
any col- 
lection 
Sweet Corn 
50 
20 
5,150 
415 
8% 
24.5% 
1% 
Beggar-ticks (Bidens 
.sp.) 
9 
7 
800 
66 
8.2% 
19% 
0% 
Pigweed {Amaran- 
thus retroflexus L.). 
9 
5 
850 
119 
14% 
24% 
7% 
Horse weed {Krigeron 
canadensis L.) 
1 
1 
100 
9 
9% 
Cocklebur (Xanthi- 
1 um sp.) 
10 
6 
1,050 
67 
6.4% 
15% 
1% 
Barnyard grass {E- 
chinochloa crusgal- 
li (L.) Beauv.).. . . 
8 
5 
750 
72 
9.6% 
20% 
4% 
Smartweed (Polygo- 
num sp.) 
7 
5 
650 
43 
6.6% 
18% 
0% 
Dahlia (Dahlia sp.). . 
4 
2 
400 
26 
6.6% 
12% 
3% 
Prince’s feather {Po- 
lygonum orientale 
L.) 
1 
1 
50 
2 
4% 
Hemp {Cannabis sa- 
liva L.) 
2 
1 
200 
9 
4.5% 
7% 
2% 
Flase ragweed {Iva 
xanthifoha Nutt.). 
1 
1 
100 
17 
17% 
