NOTES ON THE YELLOW-BEAR CATERPILLAR. 61 
a large cluster of eggs of this species was taken on a sugar-beet leaf 
at Rocky Ford, Colo. August 13, at a seed farm east of Rocky Ford, 
many clusters of eggs, thousands of newly hatched larvae, and some 
larvae one-third grown were found on a large patch of rhubarb. A 
dozen or more moths were also observed on the rhubarb, some of 
which were depositing eggs. Rhubarb, possibly because it provided 
so much protection to the moths, was a favorite food plant and great 
numbers of eggs were deposited on it. The larvae, after partially or 
completely stripping the large leaves, spread to other plants. 
By August 24 larvae, varying in size from quite small to one-half 
grown, were seen in many beet fields. Infestation was usually con- 
fined to spots, often only a corner of a field being infested. 
By September 6 infestation had become general and there was 
probably not a field of beets in the Rocky Ford district in which 
larvae were not present, at least in small numbers. At this date a 
large portion of the larvae were over half grown. The worst infesta- 
tion occurred within a radius of 2 \ miles from the town. With few 
exceptions, the beets outside of this area were not seriously infested, 
and later examinations throughout the infested portions of the valley 
showed that the worst infestations were close to the towns, although 
in some cases the infestation extended miles beyond them. 
September 11 the first cocoon was found, containing a larva which 
pupated a few days later. By September 14 many larvae had matured, 
left the beets, and were seen hurrying away in search of places for 
pupation. September 17, several larvae were found dead from a 
fungous disease. By September 20, although larvae were still 
abundant and as many as 16 individuals were counted on a single 
beet, many had matured and crawled under heaps of weeds, grass, 
rubbish, boards, etc., along fences and irrigation ditches, and had 
formed cocoons. Of 20 cocoons which were examined at this time, 
19 contained live larvae and 1 a new, soft pupa. Seventeen of these 
larvae pupated within the next three or four days. At this date, 
September 20, a large acreage of the beets had been badly defoliated. 
In some fields nothing remained of the foliage except a few young 
leaves (which the larvae usually avoided), the petioles, and some of 
the larger veins of the older leaves. 
September 22, in the corner of one beet field, over an area about 
three-fourths of an acre in extent, many larvae were troubled with a 
fungous disease identified as Botrytis bassiana Bals. About 2 per 
cent of the larvae had died from this cause. It was noted September 
25, and later throughout the Rocky Ford district, that the disease 
had not spread and that diseased larvae did not exist or were rare> 
except in this corner. 
By September 27 larvae were noticeably less abundant and many 
defoliated beets were putting out new tops. Before the Diacrisia 
