31 
a Northern as well as ISoiithern one, but it appears U) be more injurious 
to eorn in the South. The latter name serves to distinguish it from its 
con<iener, />. loiif/icornis, the corn root-worm of the West and ZSorth. 
The beetles have an especial fondness for beans and soy beans, and 
were observed the past year feeding on the upper surface of the leaves 
early in Septend)er. They make many small, irregular holes in a leaf, 
not at all like those of the bean leaf-beetle, which are large and rather 
regularly rounded. The beetles were observed feeding upon bean pods 
in the same manner as 7). vlttafa, also on the i)etals and other i)ortions 
of the flowers of cultivated Bidens and chrysanthemums on the Depart- 
ment grounds. They were noticeably much more abundant on a species 
of Bidens with orange raytlowers than upon another which had white 
ray flowers. 
A young wheel-bug {Prioniclus cristatus Linn.), about one-fourth 
grown, was observed June 28 with a beetle of this species impaled upon 
its proboscis. This bug evinces no partiality for beetles, but was noticed 
in the last week of October feeding upon the clover leaf weevil, rhi/tono- 
mus imnciatuii. 
I have been much interested in the perusal of Mr. F, M. Webster's 
article on the genus Diabrotica published in the Journal of the New 
York Entomological Society for December, 1895; but when the subject 
of the probable inedibility of Diabrotica by birds was raised, without 
any cause being assigned for this apparent protection beyond the sup- 
})osed ''warning'' coloration of these beetles, I took the trouble to 
inquire into the matter to this limited extent. The beetles have, to me, 
a perceptible odor, similar to that of ladybirds, but so faint as to 
hardly seem worth considering as a means of defense. In resi)ouse to 
inquiry of my neighbors, Messrs. Beal and Judd, of the Division of 
Biological Survey of this Department, I am informed that from exam- 
ination of many stomachs it has been ascertained that many birds feed, 
and to a considerable extent, on both IMahrotica 12punctata and vittata, 
preferably upon the former. This preference is due, evidently, to the 
larger size of this beetle, its more conspicuous coloration, its greater 
variety of food plants, and its habit of feeding during the day in more 
exposed situations. 
From the past year's observations of D. 12-iyunctata it is obvious 
that the final disappearance of the beetle is limited only by the supply 
of natural food remaining for it. All through the prolonged rainy 
spell which lasted from the latter days of October until the middle of 
November these beetles were always to be found on the Department 
grounds, and in numbers, as often as the rain ceased. November IG the 
beetles were still present in abundance upon the flowers of Bidens, 
although many blossoms had wilted and died. On the following day 
the weather turned much colder, the plants were mowed down, and no 
more beetles were to be seen. Obviously this is one of our latest 
beetles. 
