Wa SeeDeeAl Be eas Ula e2. anti Vale Issued December 8, 1910. 
SOME INSECTS INJURIOUS TO TRUCK CROPS. 
NOTES ON THE CUCUMBER BEETLES. 
By F. H. Cuirrenpen, 
In Charge of Truck Crop and Stored Product Insect Investigations. 
INTRODUCTORY. 
Among insects injurious to useful crops are many species of Dia- 
brotica, most of which for convenience we may term cucumber 
beetles, the term including such species as feed upon cucurbits and 
similar plants. The commonest and best known examples are the 
striped cucumber beetle? (Diabrotica vittata Fab.), the twelve-spotted 
cucumber beetle or southern corn root-worm (D. duodecimpunctata 
Oliv.), and a western species related to the last, known as Diabrotica 
soror Lec. All of these are of the highest economic importance. The 
first mentioned is one of the most injurious species affecting truck 
crops; the second is very troublesome in the Southern States, while 
the last is about equally injurious in the Pacific region. In 
addition to these we now know of several other species which 
habitually or occasionally affect truck crops. In all there are a full 
score of species of this genus and two subspecies. A few of these are 
more often found on corn and grasses, hence will not be considered in 
this article. 
The notes which follow are supplemented by a more detailed article, 
by Mr. H. O. Marsh, on the same and other species. The species 
which the writer will consider have never been treated at any length 
in a departmental publication, and the illustrations are here presented 
for the first time. 
aThe economic treatment of the first two species mentioned, the striped and the 
twelve-spotted cucumber beetles, is given in Circulars Nos. 31 and 59, respectively. 
In the latter, the western corn root-worm, which is more of a field-crop insect, is also 
treated. These publications may be obtained free of charge on application to the 
Secretary of Agriculture. 
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