INJURIOUS INSECTS OF I909 AND IQIO. 87 
On June 2d the larvae were show- 
ing a noticeable tendency to work 
down toward the bases of the leaf 
blades, and even to work into the leaf 
petioles to a considerable extent. The 
largest of the giant bur-elders were 
about four inches tall at this time. 
Leaves showing this mining work, 
and two of the larvae, were bottled 
in alcohol and formalin. By June 4th 
the larvae had in many cases taken to 
boring into the stalks of the young 
bur-elders, the tallest of the weeds 
at this time being about five inches 
tall and about one-tenth inch through 
at the base. By July 7th many of the 
first plants attacked were dead, hav- 
ing been completely destroyed by the 
Fig. 41. 
leaflet shown in Fig. 40, 
Franklin. 
Larvae of Papaipema sp., 
much 
Fig. 40. 
mining in 
enlarged. 
The larva of Papaipema 
sp. mining in leaf of Giant bur- 
elder seedling. Franklin. 
borers, and many of the 
berers were in their sec- 
ond plants. The stalks of 
the second plants attacked 
were at this time about 
twenty-four inches long 
on the average, and the 
galleries in them averaged 
about four inches in 
length, ranging from two 
and one-half inches to six 
inches. By July 22d the 
caterpillars had reached a 
length of from one inch 
to one and one-quarter 
inch, the galleries much 
longer than the longest 
ones were on July 7th: 
One plant was found har- 
boring two of the cater- 
pillars. Its stem at this 
date was’ twenty-three 
inches long. The entrance 
