2i]Q Fiftieth Report on the State Museum 



ten were frequently found on a single leaf. They probably appear in- 



May or June, when they deposit their eggs on the under side of the 



leaves, which hatch into small grubs that burrow into the leaves and 



feed upon the substance beneath the surface, forming blisters near the 



edges which usually extend to the midrib. * * * They change 



within the blister to the pupa form, from which the beetles soon emerge 



and feed on the surface of the remaining unaffected leaves. The blisters 



formed by the larvce and tlie leaves skeletonized by the beetles, * * * 



cause the leaves to turn brown, wither and fall. * * * 'pj^g beetle 



was also taken feeding on the leaves of the locust at Morgantov/n, on 



June loth, and at Kanawha Station on June i6th. 



" Like the plum curculio, it is the habit of this beetle to fall to the 



ground when alarmed, and in the case of valued shade trees, it may be 



possible to destroy them by the jarring process which is successful with 



the curculio. Their habit of feeding on the upper surface of the leaves 



would make it easy to treat them by spraying the trees with poisoned 



liquid." 



Food Plants. 



Although the locust is the natural food-plant of this insect, it seems 

 not to be entirely confined to it, for Dr. Dimmock has reported it as 

 extending its devastation to a number of other trees. 



A correspondent of the American Entomologist (Vol. iii, p. 151), 

 represents it as devouring the advanced foliage of Siberian crab-apples 

 in the first week of May, and "in the wild woods, the tender leaves of 

 Ulmus America?! a. '^ Finding insufticient food in the mined Robinia 

 leaves, they attack the young leaves of red-oak {Qiiercns rubra), leaving 

 other species of oaks near by, untouched. Mr. Hopkins (loc. cit.) found 

 the insect feeding on the foliage of white oak, beech, birch and hawthorn 

 in West Virginia, and Mr. Chittenden (/. c.) records instances of their feed- 

 ing on red clover, hog peanut iFakata comosa which is the Amphicar- 

 pica mouoica of Gray's Manual) and soja beans. 



Dr. Harris' Account of the Insect. 

 According to Dr. Harris, the beetles may be found pairing in Massa- 

 chusetts, in the middle of June and laying eggs on the leaves of the 

 locust trees which are transformed to the perfect insect in August. 

 "They measure nearly one-quarter of an inch in length, and are of a 

 tawny yellow color, with a black longitudinal line on the middle of the 

 back, partly on one and partly on the other wing-cover, the inner edges 

 of which meet together and form what is called the suture ; whence the 

 species was named Hispa suturalis by Fabricius ; the head, antennae,- 



