84 
SOME INSECTS INJURIOUS TO TRUCK CROPS. 
as recorded at the local weather station, ranged from a minimum of 
60.9° F. to 94.4° F. 
Observation has not been carried far enough to enable the writer 
to state positively the number of generations in this region. 
OBSERVATIONS ON DIABROTICA DUODECIMPUNCTATA Oliv. 
The twelve-spotted cucumber beetle {Diabrotica duodecim punctata 
Oliv.) occurs only in small numbers in southern Texas, and no com- 
plaints of injury were received concerning it. 
On February 5 four mature larvae were found feeding on the roots 
of sorghum at Harlingen, Tex. February 7 one of these made its 
cell; on the 15th it pupated, and on the 25th the adult developed. 
The other beetles developed a day or two later. 
On May 12 a female with greatly distended abdomen was placed in 
confinement and deposited eggs as follows: 
Record of egg deposition of a single female beetle of Diabrotica duodecim punctata in con- 
finement May 12, 1909. 
1909. 
Number 
of eggs. 
1909. 
Number 
of eggs. 
May 14 
68 
75 
63 
67 
55 
110 
May 29 
38 
19 
20 
(O) 
Mav 16 
May 19 
May 24 
June 8 
May 26 
Total 
May 27....... 
515 
a Beetle died. 
This gives a grand total of 515 eggs from one beetle. 
The record for the eggs which were deposited May 14 is as follows: 
Detailed record for the 68 eggs of Diabrotica duodecimpuncta'i deposited May 14. 1909. 
May 14 68 eggs deposited . 
May 20 68 eggs hatched. 
May 31 First larvae made cells. 
June 4 First larvae pupated. 
June 10 First adults developed . 
June 12 First adults issued from cells. 
June 14 All adults had issued. 
The stages were as follows : 
Days. 
Egg stage 6 
Larval stage 15 
Pupal stage 6 
Total. 
This species proved very hard to rear and only a small proportion 
of the larvse reached the pupal stage. The larvae were placed in large 
jelly glasses and fed on sorghum cane. 
