. 350 

 THE POTATO-BUD WEEVIL. 



{Anthonomns uifjrinus Boh.) 

 By F. H. Chittendkn. 



The recent outbreak of Anilumomus signatus Say or vstrawberry wee- 

 vil induced tlie writer to investigate the habits of other bud feeding 

 Coleoptera. A rather common species in tliis h)cality closely resem- 

 bling A. signatus both biologically and structurally is A. nigrimis Boh. 

 It breeds in the unopened llower-buds of solanaceous 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 Solanaceae, 

 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 miiy 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 Ave 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, 

 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-uettle, 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. 



