ON ROSES. 129 



to feed upon the leaflets, working from the edges. Many of 

 the Sawflies — and especially the one under notice and a species 

 which infests Filbert-trees — -are very restless on being disturbed, 

 and assume what appears to be a defiant attitude ; this is parti- 

 cularly well shown by the illustration. There are several other 

 species of Hylotoma affecting Roses, but none more destructive 

 than the one just described. 



To the genus Eriocampa belongs another most voracious 

 species, E. roscE. This feeds very differently from H. ros(E and 

 its allies, for instead of devouring the leaflets in their entirety 

 it attacks only their epidermis. This characteristic betrays 

 at once the presence of the caterpillars of E. rosce, even if 

 the objectionable-looking slug-like creature were itself not in 

 evidence. This is a very near relative of the Slug-worm (so- 

 called) of Pear- and Apple-trees. The eggs are deposited 

 in May by the female Sawfly (which it would serve no good 

 purpose to describe here) in the midribs of the leaflets, and they 

 are hatched out in some two to three weeks. The resulting 

 larvae are yellowish-green, and when full-fed they pupate in oval 

 cocoons spun beneath the surface of the soil. 



A very distinct species is Pamphilius {Lyda) inanita,, which 

 feeds protected by a case, mimicing in this particular one of the 

 objectionable Clothes-Moths. There are also other Sawflies, all of 

 which feed on the leaves ; for though there is a species which 

 feeds on the pith it has been so seldom recorded that it is hardly 

 worth taking into account. By many the pith-feeding moth 

 caterpillar already alluded to is frequently mistaken for it. 



Roses which have been sprayed with a weak arsenical solution 

 several times before the blossoms expand will ' be less likely 

 to harbour Sawfly caterpillars than those not so treated ; but 

 many growers have strong prejudice against the use of these 

 arsenites. In such cases, powdered hellebore dusted on the 

 leaves in the early morning when they are damp from the dew 

 w^ill be the best means of keeping Sawflies away, or destroying 

 any larvae which have taken up their abode on the plants. The 

 caterpillars may also be shaken from the trees over a cloth, and 

 collected and destroyed ; but the hellebore (which by the way 

 is a strong poison) is far more effectual and practical. As the 

 Sawflies usually pupate just beneath the surface of the soil, it is 

 a good plan when a tree has been severely attacked in summer, 

 to remove the surface soil to a depth of two or three inches, 

 replacing it with fresh. This is best done in late autumn. 



K 



