422 CONIFERS. 



mulates in such masses as to snap in sunder or tear from 

 their sockets the long and often nearly horizontal branches 

 of this tree. 



The insects which feed upon the Pinus sylvestris are 

 numerous, and belong to various orders of the class : some 

 live upon the foliage, others upon the wood, either in a 

 fresh or decaying state ; others again are subcortical feeders 

 and live upon the inner portion of the bark, and some 

 few confine their depredations to the decaying roots. Most 

 of the leaf-eaters consist of the caterpillars of the Lepido- 

 ptera, and those of the Tenthredinous section of the Hymen- 

 optera. Of the Sphinc/idce, there is the caterpillar of the 

 Sphinx pinastri) a large and beautiful species but of rare 

 occurrence in Britain. Eutrichia pini, belonging to the 

 Linnean Bombyces, whose caterpillar is covered with hair 

 which causes great irritation when handled, is also occa- 

 sionally met with. Of the Lithosiid<£ three or four species 

 feed occasionally upon this fir. Amongst the Noctuidce, 

 is Achatia piniperda, fortunately of rare occurrence in 

 this country, but sometimes very destructive to the con- 

 tinental Pine forests. Of the Geometridee the Bupalus 

 piniarius is far from uncommon in the north of England, 

 and appears to be upon the increase. Of the smaller moths 

 belonging to the Tortricid<z and Tineidte there are several 

 species, among them (Ecophora oliviella, whose caterpillar 

 subsists upon the half-decayed liber of dying trees. 

 Amongst the Tenthredhue the pseudo caterpillar of Lopliy- 

 rus pini sometimes commits great ravages, but its visits 

 are uncertain and at considerable intervals. Though most 

 of the wood-borers or internal feeders belong to the Coleo- 

 ptera, we may here particularize the larva of the genus 

 Sirex, Linn : ( Urocerus Geoff.) belonging to the Hymen- 

 opterons order. In a perfect, or winged state, some of 



