424 
Journal of Agricultural Research 
Vol. XXI, No. 6 
The full-grown larva (PI. 76, U; fig. 16) is less translucent and the 
color is more grayish white than in the previous instar. There is a 
darker area almost the full length of the larva due to the contents of the 
digestive tract. The general shape of the larva is the same as in the 
previous instar. There is a distinct lateral invagination of the last 
abdominal segment. The dorsal folds are more prominent than in the 
previous instar, and there are usually more of them. The setae are more 
prominent than in any previous instar except the first. Four full-grown 
larvae averaged 2.485 mm. in length and 0.735 mm. in greatest width. 
Head as in previous instar. Mandibles (PI. 76, R) very stout and heavily 
chitinized. The labrum (PI. 76, S) is a large, rectangular, fleshy piece 
that almost covers the mandibles. On the inner surface near the distal 
margin are from 5 to 7 prominent denticles or lobes which are apparently 
very heavily chitinized; the labrum also bears 2 minute setae. The 
maxillae and labium (PI. 76, T) are fused and only very slightly^ chitinized 
on the surface; they bear 6 minute setae and in addition 2 groups of slight 
Fig. itr—Eupclmus allynii; Lateral view of full-grown larva. X 3°-6- 
elevations or tubercles containing 3 elevations each, 2 groups containing 
2 each, and 4 single scars or elevations. All are arranged as in Plate 76, 
T. Spiracles as in previous instar. Setae as follows: 14 on the first 
thoracic, 10 on each of the second and third thoracic segments, 4 on each 
of the first 5 abdominal, 6 on each of the last 5 abdominal segments. 
Setae arranged as shown in figure 16. 
The number of larval instars and molts were ascertained in the manner 
described for Ditropinotus aureoviridis , page 411-412. There were found 
to be 4 larval molts with 5 pairs of larval mandibles (PI. 76, N-R) as for 
D . aureoviridis. The manner of feeding and locomotion is also similar 
to that of D. aureoviridis. Thirty-two larvae reared in glass cells in 
1918 became full-grown in from 7 to 12 days, depending upon weather 
conditions. The average length of this period was 9 days, or an average 
of about 2.25 days per molt. Twenty-seven of these larvae were inactive 
for from 2 to 17 days, an average of 5 days, before beginning pupation. 
In 1917, 28 individuals averaged 16 days in the larval stage from egg to 
prepupa. 
