4 BULLETIN 422, U. S. DEPARTMENT OF AGRICULTURE. 
TaBLe I.— Mean maximum and minimum temperatures at Baton Rouge, La., during | 
June, July, and August, 1915, when life-history studies on eggplant tortoise beetle were 
conducted. 
ee Bas of mean in- — 
- : eather sec tempera- | 
Bureau, mean {aseciery mean SSS those . 
Peri temperatures.! = — of U. S. Weathe | 
eriod. Bureau. | b 
Max. Min. Max. Min. Max. | Min 
°F IN ed Pe ae fies oe a 
JUNG Sos ee ee a aes 91.5 PAR 94.9 73.9 3.4 1 
Daly. 32 se ee SE he Eee Clee en ee 92.5 71.9 95. 4 74.8 2.9 2. 
AvpSt 52k ey eect hee ee ae 91.3 70.0 92.1 74.0 8 
1 Climatological data, Louisiana section, for months of June, July, and August, 1915, by Isaac M. Cline, ~ 
pp. 46, 54, 62, New Orleans, La., 1915. 
LENGTH OF LARVAL PERIOD. 
The length of the larval period has been found to vary greatly in” | 
the insectary. Forty-three larve that were kept under observation 
during June and July required from 12 to 20 days to develop, 17 days | 
being the average. No satisfactory reason for this wide difference _ 
can be suggested. Larve that issued on the same day and which 
were apparently kept under similar conditions pupated, im some J 
cases, six days apart. On eggplant grown under cages out of doors § 
the larval period was completed in 12 days during June. 
The larve are sluggish and occur on both sides of the leaves, in 4 
which they eat more or less circular holes. When the larve are 
young these holes are small in size, but with the growth of the indi- _ 
vidual there is an increase in the quantity of tissue removed. 
LENGTH OF PUPAL STAGE. 
The pupal period occupied from two to seven days in the insectary e| 
‘during June and July, though most of the individuals remained in 
the pupal stage from four to five days. 
LIFE AND HABITS OF ADULTS. 
The adults, even during the summer, live for a period of several 
weeks. In the insectary one individual, a female, was kept alive 
from May 22 to October 9, two months after it had ceased to lay eggs, 
and others have lived for two or three months. The winter months — 
are undoubtedly passed in the adult stage. 
The injury done to the leaves of eggplant (fig. 3) by the adults is 
of the same character as that due to the larve, the feeding of the 
beetles producing holes which are somewhat circular in outline. 
NUMBER OF EGGS DEPOSITED BY ONE FEMALE. 
On July 4, beetles that had issued in rearing cages in the insectary, © 
none of which had begun to oviposit, were placed together on egg- 
plant leaves. The first eggs were noted on July 6. when the beetles © 
. 
i 
