BIOLOGIC NOTES ON SPECIES OF DIABROTICA IN 
SOUTHERN TEXAS. 
By H. O. Marss, 
Agent and Expert. 
INTRODUCTION. | 
During the first half of the year 1909, while engaged in an investi- 
gation of insects injurious to truck crops, an opportunity was pre- 
sented to make a study of the species of leaf-beetles of the genus 
Diabrotica occurring at Brownsville, Tex., and vicinity. 
In the present paper the species considered are Diabrotica balteata, 
D. picticornis, D. vittata, and D. 12-punctata. The first two species 
are rather more abundant in Texas than elsewhere in the United 
States, this being especially true of the second. The other species 
have a more general distribution. 
I am under obligations to Mr. D. K. McMillan for the descriptions 
of the early stages of D. balteata and to the late Dr. C. F. Wheeler, of 
the Bureau of Plant Industry, for identification of the food plants 
mentioned in the text. 
OBSERVATIONS ON DIABROTICA PICTICORNIS Horn. 
The painted cucumber beetle (Diabrotica picticornis Horn) was 
extremely rare in southern Texas during the season of 1909, and only 
occasional specimens were observed, although during May and June, 
1908, Mr. McMillan noted them in abundance at Brownsville, Tex., 
eating the blossoms and foliage of cucurbits, especially that of Hub- 
bard squash. 
During 1909 the first specimen, a female, was taken March 1 on a 
Verbesina blossom. March 15 a female was taken feeding on cucum- 
ber foliage and continued in captivity until May 22, but she deposited 
no eggs. April 15, a half dozen individuals were observed on cym- 
lings. The females appeared to be well filled with eggs. Of two 
which were placed in confinement at that date, one was still living 
June 14, but neither deposited eggs. 
OBSERVATIONS ON DIABROTICA BALTEATA Lec. 
The belted cucumber beetle (Diabrotica balteata Lec.) is active dur- 
ing the entire year in southern Texas, and is by far the most injurious 
and common Diabrotica in the lower Rio Grande valley. It is almost 
omnivorous and injuries caused by it are thus widely distributed and 
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