55 



more 



One of our allied beetles, Colaspis Jlavida, 

 Say., feeds also in the larval state upon the root- 

 lets of the strawberry. Fig. 62 represents the 

 larva, Fig. G3 the mature insect. 



We now come to the extensive genus Chry- 

 somela (golden apples), which contains our largest 

 beetles of this family. The most generally known, 

 as well as the most generally hated of these is 

 G. decem-lmeata, Say, the ten-lined chrysomela, or as 

 commonly called the Colorado potato beetle. This insect has already 

 been described and frequently mentioned in our Reports, and its 

 appearance and habits are so well known to all agriculturists that 

 only a very brief account of it must be given here. Over sixty years 

 ago, in 1819 or 1820, it was discovered by Say along the Upper 

 Missouri, near the base of the Rocky Mountains, where it fed upon Solanum rostratum, 

 a wild plant belonging to the same genus as the cultivated potato (Solanum tuberosum). 

 Its discoverer had probably no idea that at some future day it would so far extend its 

 range and prove so noxious an insect, but as the country became settled it was found 

 transferring itself to the potato fields, where it obtained a more abundant and constant 

 supply of food, and where it increased in numbers proportionately. By 1861 the beetles 

 had become so numerous in Kansas that over two bushels of them were gathered in one 

 garden. During the last twenty years they have rapidly extended their range eastward, 

 and in the past summer they have been reported from Nova Scotia. While they still 

 cause much trouble and a certain amount of loss to pototo growers, they are no longer 

 feared as they were when their ravages were first made known. Paris green and London 

 purple, when properly applied, have proved efficient destroyers, while planting early 

 ripening species of potatoes, ensures their maturing before the beetles become numerous 

 enough to do much injury to them. Gradually also insect enemies have increased in 

 kind and number, among which may be named Fodispus spinosus, Dallas, the (Spined 

 Soldier-Bug, Fig. 64) ; Perrillus circumcinctus, Say (the Belted Soldier-Bug, Fig. 65) ; 

 Harpactor cinctus, Fab. (the Many- banded Robber-bug, Fig. QQ) ; Lydella dori/j^horce, 



a 



Fig. 6.5. 



Fig. m. 



Riley, a two-winged fly, of which the larvae are parasitic in the 

 grubs of the beetle; Lebia gi'andis, Hentz (Fig. 67, where it is 

 shown magnified, and also of the natural size) ; and other beetles 

 belonging to the Carabidae, and several species of Lady-birds 

 (Coccinellidse), of which the largest is Mysia lo-punctata, Oliv. 

 (Fig. 68). Notwithstanding the aid thus rendered to man it will 



Fig. 67. 



Fig. 68. 



be a very long time before 

 the beetles are so far exter- 

 minated as to be rarities. 

 The patches of yellow eggs 

 upon the leaves, the loath- 

 some yellowish-red, black- 

 spotted larvaj destroying the 

 tops, and the beetles crawling 

 in striped yellow and black 



