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UNITED STATES DEPARTMENT OF AGRICULTURE 
fjjjl BULLETIN No. 264 
Contribution from the Bureau of Entomology 
L. O. HOWARD, Chief 
Washington, p. C. T June 15, 1915. 
THE VIOLET ROVE-BEETLE. 
I 
By F. H. Chittenden, Sc. D., 
Charge of Truck Crop 1 and Stored Product Insect Investigations. 
% 
INTRODUCTION. 
Beginning with the year 1901 a small dark-colored rove-beetle, 
known to science as Apocellus sphaericollis Say, has been reported as 
an enemy to violets and other succulent ornamental plants in the Dis- 
trict of Columbia and from St. Louis, Mo. This insect is a very 
common one in the United States and is quite generally known as a 
scavenger, feeding on humus and decaying vegetation and similar 
matter. That it feeds on violets as well as on a variety of other vege- 
tation is now undoubted. Informants have furnished abundant proof 
of this in the eaten flowers and leaves, while beetles in confinement 
in the writer's laboratory were observed by him to attack violets and 
other plants. Nor does the insect confine itself to plants grown in- 
doors or in gardens, since in its Washington occurrence the violets 
were grown in hothouses and at St. Louis the various plants affected 
were growing in the open. There is no doubt, however, that although 
the habit of the insect of feeding on delicate flowers and leaves is 
well established it is nevertheless an acquired taste, the insect living 
normally like others of its kind on old, dead leaves or in soil which 
has been coA 7 ered by leaves over winter. 
Undoubtedly injury by this species is more extensive than our 
notes show. This may be ascribed mainly to the resemblance of this 
insect, to the casual observer at least, to an ant, and to the fact that 
the beetles swarm in numbers on plants in the manner of ants. The 
year after the first report of injury by this species so many com- 
plaints of injuries by ants in greenhouses were made that the Florists' 
Exchange 2 asked the writer for an article bearing upon this subject. 
1 A large proportion of the insects which infest the garden also infest greenhouses, as 
in the present instance. Next to roses, violets are favorite flowers grown in this and 
some other countries. In Bulletin No. 27, new series, Bureau of Entomology (out of 
print, but available in libraries), a somewhat comprehensive publication on violet insects 
was furnished. 
2 F. H. C. A violet pest. In The Florists' Exchange, v. 36, No. 23, p. 1216, Dec. 6, 
1913. 
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