INSERTS IN RELATION TO PLANTS. 545 



whole districts of orchards, as Peck has related in a distinct treatise *. 

 The larva of Lyda pratensis also, which lives upon the fir., a short time 

 since, in the vicinity of Muskau, in Silesia, committed dreadful devas- 

 tation, according to the communication of K. Hapf t. 



But in no order are leaves used so universally for food as among the 

 Lepidoptera, of which the majority as caterpillars consume them. We 

 imagine we shall give a sufficient proof of this by mentioning some of 

 the numerous trees and plants indigenous with us, and which are 

 eaten by caterpillars. The oak, in the first place, feeds innumerable 

 caterpillars, for instance, Gastropacha quercus, Smerinlhus quercus, 

 Harpy a Milhauseri, Nolodonla camelina, innumerable Noctuce, and 

 Geometers ; according to a calculation of Roesel's, this tree supports 

 in its several parts and organs about two hundred distinct species of 

 insects, whence it will be easy to deduce their relation to the rest, as 

 well as of insects to the vegetable kingdom in general. Thus every 

 forest tree has not merely one, but three, four, and even as many as a 

 dozen caterpillars which feed upon its leaves, and which often seriously 

 injure them. We will merely refer to the destruction occasioned by 

 Liparis diapar to poplars, L. salicis to willows, L. chrysorrhea, L. 

 nudibunda, L.Jascelina to different fruit trees, L. monacha to the fir, 

 and a multitude of others, which are^known as tree and forest de- 

 stroyers. The number of injurious forest caterpillars is so large that 

 we cannot wonder at the great devastation we so frequently hear com- 

 mitted by them. Thus there are found upon the pine, besides those 

 already enumerated, Gastropacha pint, G. pilyocampa, Sphinx pi- 

 nastri, Noctua (Trachea, Tr.) piniperda, Lithoria quadra, Geometra 

 (Fidonia, Tr.), piniaria, G. (Ellopia, Tr.) prasinaria, G. (Ell. Tr.) 

 fasciaria ; Tinea resinella, which occasions the escape of resin from the 

 young twigs of the fir ; T. dodccclla, T. strobilella, T. pinella, &c., 

 which dwell partly in the young buds, and partly in the eves of the 

 firs. We will not extend this list to other forest trees, but refer at 

 once to Bechstein's^ Natural History of Injurious Forest Insects, 

 where there is ample detail. We will only further mention that manv 

 of our fruit trees support their peculiar enemies, among which the cater- 



* W. Peck, Natural History of the Slug-worm. Boston, N. A., 1799. 8vo. 

 f Bemerkungen uber Raupenfrass v. K. Hapf. Bam berg, in Aschaffenberg. 1829. 8vo. 

 + Bechstein's Naturgeschichte der schadlichen Forstinsekten. Leipzig, 1805, 3 vols. 

 4to. 



N N 



