132 ON THE CATERPILLARS 



species, I have satisfied myself that it is not the true Ten- 

 thredo Cerasi, of Linnaeus, whose name had been applied to 

 it, but whose description both of the habits and characters of 

 that species disagree with those of the insect produced from 

 these slimy larvae ; indeed, Klug and Hartig applied to it the 

 Fabrician name Tenthredo JEthiops (a name given by Fa- 

 bricius to an English insect in the Banksian Cabinet), but 

 repeated observations have disproved the correctness of the 

 nomenclature of these authors : the insect is, in fact, the 

 Selandria at?-a, of Stephens. 



Another saw-fly larva, which is very common in gardens 

 and very injurious to rose trees, next merits our attention, the 

 more especially as it happens to be the true Tenthredo 

 jEthiops. It is in the month of June, when the rose tree 

 needs all its energies for the development of fine bloom, that 

 many of the leaves turn pale brown, looking as though they 

 had been scorched, the upper cuticle of the leaf being entirely 

 or partially eaten away, the lower surface being always left 

 entire. In some gardens, every rose leaf will be attacked by 

 these pests, and the injury to the plants must be considerable. 

 The larva which causes these unsightly discolorations is about 

 half an inch long; it is of a pale yellowish green colour, with 

 a darker line down the middle of the back, and an orange- 

 coloured head ; it has three pairs of jointed legs, seven pairs 

 of ventral, and two anal prolegs (making twenty-two feet in 

 all). When they have shed their skins several times and 

 arrived at their full size, they descend into the earth, where 

 they form little hollow oval cells of earth, highly polished 

 on the inside, in which they pass the winter, and wherein 

 they undergo their transformations. The perfect insects ap- 

 pear in spring, and lay their eggs on the rose leaves, and the 

 larvae begin to be hatched about the end of May. 



