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THE POTATO-BUD WEEVIL. 
{Anthonomus nigrinus Boh.) 
By F. H. Chittenden. 
The recent outbreak of* Anthonomus signatus Say or strawberry wee- 
vil induced the writer to investigate the habits of other bud feeding 
Coleoptera. A rather common species in this locality closely resem- 
bling A. signatus both biologically and structurally is A. nigrinus Boh. 
It breeds in the unopened flower-buds of solan aceous plants after the 
manner of its injurious congener in the strawberry and red-bud. 
The adult beetle resembles the latter in form, but is of a little larger 
size. In color it is uniform dull black, sparsely clothed with fine, whit- 
ish pubescence. It is commonly found on the horse- nettle (Solanum 
carolinense), and when the potato (S. tuberosum) blossoms this also is 
attacked. In food habit it appears to be restricted to the Solanacese, 
if not to the genus Solanum. 
In distribution it is also limited; evidently more so than the horse- 
nettle. Its recorded distribution is: District of Columbia, North Car- 
olina, Louisiana, and Virginia. It occurs also in Maryland, but it is 
doubtful if it extends much farther to the north. Common as is the 
species in this vicinity, it is comparatively rare in collections. 
This insect has never been reported as injurious, but as it attacks 
one of our most important cultivated food-plants, an account of its 
habits may be of interest. 
It has the same habit as A. signatus of severing the stems in which 
it oviposits, and also cuts off the buds, apparently often in pure wan- 
tonness, but in reality, probably, for food. In one potato patch near 
Washington which I visited July 4, not half a dozen flowers could be 
found, but many beetles were present. The plants had been very 
recently attacked, evidently during the preceding night, as the 
majority of the buds were still upon the stems, although many were 
severed and the remainder dropped off at the slightest touch. All but 
a few of the smallest buds were severed. In some instances, a bunch 
or cluster of four or five minute buds had all been cut off by a single 
girdling of their common stem. It hardly seemed possible that all of 
these buds, the majority of which barely measured an eighth of an inch r 
and were too small for the development of the weevil, could have been 
cut off by this insect. But the ends of the stems presented the same 
appearance as did those of the horse- nettle, which were cut off after 
oviposition. 
The explanation of this attack would appear to be that a lot of plants 
of the horse-nettle, which appears to be the favorite larval food-plant of 
the species, had been cut down in the immediate vicinity, and the adult 
beetles had found the juice of the stems of the cultivated Solanum 
quite to their liking. 
