Chapter XV. 



INSECTS INJURIOUS TO THE PINE. 

 Pinus strobus, P. rigida, etc. 



The uumber of species here recorded as living ou the pines alone 

 amounts to from 165 to 170, while the total number will probably prove 

 to be nearly double that given. Kaltenbach in his work on Plant 

 Insect-enemies does not separate those of the pine from those of the 

 spruce, fir, and larch, but " lumps" them all together under one head, 

 whether peculiar to the pine, the fir, or the larch. This is a mistake, 

 although, as is well known, a large proportion of the insects which are 

 known in this country to prey upon the pine also occur on the spruce 

 and fir, as well as the hemlock and larch ; yet a goodly number of spe- 

 cies live exclusively on one kind of tree, notably some of those found 

 on the hackmatack or larch. We have, therefore, been careful to record 

 the insects of each tree separately. 



Kaltenbach in his ''pine" insects enumerates two hundred and 

 ninety-nine species, of which there are one hundred and thirty Cole- 

 optera, but of these about twenty species are carnivorous beetles, which 

 for the most part prey on the borers, or are scavengers, and should not 

 have been placed among the plant-eaters, but in a separate note or 

 appendix by themselves. A large proportion of the borers are Scoly- 

 tids, over twenty species being enumerated, besides about forty species 

 of the weevil family. Of longicorn borers there are in Europe about 

 twenty species. The Buprestids are less numerous apparently than in 

 iTorth America, only five species being mentioned, while as in this coun- 

 try few species of leaf- beetles prey on coniferous trees, their leaves 

 being hard and apparently lacking in nourishment for such beetles, 

 which prefer the more succulent leaves of hard-wood trees. 



Of European pine-caterpillars Kaltenbach enumerates seventy-one 

 species, none of them being those of butterflies; the proportion of silk- 

 worms (Bombyces), span-worms, or Geometrids, and of leaf-rollers is 

 much as in North America; of the Tineids only twelve species are re- 

 ported as feeding ou these conifers, and we have called attention to 

 the very small number which occur on coniferous trees in the United 

 States. 



The species of saw-flies which infest the coniferous trees of Europe^ 

 as on this continent, form a numerous company, Kaltenbach enumer- 

 ating thirty-eight. Only six flies (Diptera) are mentioned; while the 



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