77 



stance of the leaf, rather than to the feeding of the beetles on the 

 leaves. 



The nature of the damage effected ])y this insect is well illustrated 

 in an article which appeared in Voliniie III of the American Ento- 

 mologist (pp. 6i>-61) by y. T. Chambers. Injury by this species is 

 stated to have been rather general in northern Kentuck3^ "By the 

 1st of August the groves look as if a tire had swept over them; and on 

 examining the leaves in many groves almost every leaflet will be found 

 to contain a 'mine,' as the burrow of the larva is technicalh^ called, 

 and man}" of them will contain three or four, while the imago or 

 mature insect of IHh])(( sutitralls will bo found in great nmnbers feed- 

 ing externally on the leaves." 



About half of the injury was attributed to the leaf-mining locust 

 beetle, the remainder to other species of leaf-miners. 



The bibliography of this species has been ))rought together up to 

 1896 in Dr. Lintner's Twelfth Report on the Insects of the State of 

 New York for that year (pp. 2»)1:, 265), and the subject need not be 

 entered into here in detail. It should be mentioned, however, that 

 the ravages of this species had assumed sufficient proportions in West 

 Virginia to call for special investigations on the part of Dr. A. D. 

 Hopkins, these studies having been begun in 1890, the results being pub- 

 lished in a short article in Bulletin No. 16 (p. S7). In the Canadian 

 Entomologist for 1896 (p. "i-^S) the same writer mentions the destruc- 

 tiveness of this species in West Virginia, adding some new food plants, 

 and in Bulletin No. 9, n. s. (p. 20), the junior author called attention 

 for the tirst time to the fact that this species fed also upon herbaceous 

 plants, and that the larvae develop in the leaves of soy bean. Other 

 accounts, which appeared with and since the year 1896, contain little 

 more than mention by State entomologists of ravages made by this 

 insect in their respective States, all of which have been briefly brought 

 together in the introductory chapter on this species. Exceptions are 

 Dr. Lintner's article previously cited and a column article by Prof. E. D. 

 Sanderson on page 672 of American Gardening for September 30, 1899. 



FOOD PLANTS. 



This species forms a rather interesting example of an insect with a 

 well-known favorite food plant, which will also feed, even in times 

 when this plant is available, on numerous other forms of vegetation, 

 both related and otherwise. 



The prime, and no doubt the original, food of the larva and beetle is, 

 of course, common locust {Rohinla ;psendacacia)^ but there is no doubt 

 that larvae could d^welop ecjuall}" well in the leaves of other species of 

 the same genus, and perhaps of most other trees of the same family. 

 On the grounds of the Department of Agriculture at AVashington the 



