64 
THE BEAN LEAF-BEETLE. 
(Cerotoma trifurcata Forst. ) 
By F. H. CHITTENDEN, JVashington, D. C. 
The discovery the present season of a small leaf-beetle related to 
and somewhat resembling, superficially, the twelve-spotted cucumber 
beetle (Diabrotica 12-punctata), and known in collections and in litera- 
ture generally as Cerotoma caminea Fab., upon beans in portions of 
Maryland and Virginia, makes it probable that this species is on the 
increase as an enemy to beans, and that it is liable to become a pest of 
some importance to the bean crop, at least in this portion of the United 
States. 
LITERATURE AND HISTORY OF THE SPECIES. 
Recent research shows that this species was described by Forster 
in 1771 (Nov. Spec. Ins., p. 29) under the specific name of trifurcata 
and later in 1801 by Fabricus as caminea, Forster’s name antedating 
the Fabrician one by thirty years. 
What appears to be the first notice of the occurrence of this species 
on the bean, in fact the first mention of any sort of the habits of this 
species, is that published by Prof. E. A. Popenoe, in the Transactions 
of the Kansas Academy of Sciences for 1876 (p. 35). It was first rec- 
ognized in 1875 in Shawnee County, Kans., “in great numbers, eating 
the leaves of dwarf beans to such an extent as to destroy the plants.” 
Later the species was noticed by the same writer in greater or less 
abundance in other localities. 
Our next account of damage was published in the report of this 
Department for the year 1887 (p. 152). The species was found by Mr. 
F. M. Webster, at that time a field agent of this Division, at Ashwood, 
La., during April of that year infesting beans in gardens. The beetles 
first attacked the plants by eating holes in the leaves and later by 
eating out the whole leaf between the larger veins. They were also 
observed to attack the cowpea in great numbers in the same manner. 
June 22 this insect was detected by the same gentleman at Princeton, 
Gibson County, Ind., also destroying beans. 
There is in the divisional records a still earlier report of injury by 
this species. June 30, 1885, Mr. M. S. Crane, an entomologist of con- 
siderable experience, wrote that this insect, specimens of which were 
sent, was eating holes in the leaves of string beans in a garden near 
Caldwell, N. J. The beetles were said to be found on the under side of 
the leaves, and their depredations were mostly confined to one end of 
the patch. Injury was not reported to be serious, but it was surmised 
that the species might prove a pest under circumstances that would 
favor its increase. 
The species was next reported by Professor Popenoe, who found it 
injurious to the bean in Kansas in 1889 (see Second Rept. Exp. Stat. 
