Doering: Lepyronia quadrangularis. 539 



Ashley (1919) reports an Aphrophora in England which causes 

 serious damage to roses during June and July by weakening the 

 young shoots and buds by extracting the sap. Harris (1862) re- 

 ports Clastoptera protons as doing great injury to the cranberry 

 crop in some parts of Massachusetts. The most destructive frog- 

 hopper is the sugar-cane froghopper, Tomaspis varia Fabr., which 

 is estimated by Urich (1913) as destroying ten per cent of the sugar 

 crop of Trinidad. The damage which is done is called "blight" and 

 consists of a withering of the leaves of the canes and a stunting of 

 the stem. This is accomplished chiefly by the nymphs feeding on 

 the roots, although the feeding of the adults on the leaves of very 

 young plants may also cause it. Williams (1923) reports Clastop- 

 tera theohromce Wills as destroying the flowers of the cacao in 

 Panama. 



No records of serious damage caused by Lepyronia quadrangularis 

 have been found. Fitch (1856) records it on grape. The writer has 

 found it on several economic plants, such as timothy, black rasp- 

 berry, wheat and sweet-clover. Most of these, excepting wheat, 

 were isolated plants or small groups of them, and therefore were 

 not of much importance. In the case of the wheat, however, the 

 matter was more serious. A good many stalks of wheat were 

 found bearing spittle masses. These occurred chiefly at one side of 

 the field next to the weeds, bordering a woods, and evidently they 

 had migrated from the weeds to the wheat. In all cases where the 

 nymphs were feeding on the wheat the heads were half the size of 

 the good heads. Nine good heads were averaged, and the number 

 of kernels was thirty-four to a head. Eleven poor heads were 

 averaged, and the number was only ten, which makes an ap- 

 proximate loss of 33 per cent. From these observations, as well as 

 those on the life history, the following conclusions can be drawn: 

 That the insects by sucking the plant juices really cause consider- 

 able damage to the host plant; and they may become a menace 

 to certain cultivated crops by their ability to migrate from one plant 

 to another, and because, unless disturbed, they are so free from 

 parasites and predators,- they may greatly increase in number. 



