RAVAGES OF CATERPILLARS. 213 



thcin in due bounds, the caterpillars ofthis moth alone, 

 leaving out of consideration the 'iUOO other IJritish 

 species, would soon destroy more th«n half of our ve- 

 getation. 



The caterpillar just mentioned, amongst other pot- 

 herbs attacks colcworts and cabbage; and may some- 

 times be found there aloni^ with another, not uncom- 

 mon, but seldom very destructive, called by collectors 

 the burnished brass {Plusui cln'ijsilis), which diflers 

 httle from the caterpillar of the y moth, except in be- 

 ing of a brighter green. Another, called the old gen- 

 tlewoman [jMumcslra brassicoi, Tkeitsciie), is so 

 destructive to cabbages in Germany, that the gar- 

 deners gather whole baskets full and bury them ; 

 but as Rb"sel remarks, they might as well endeavour 

 to kill a crab by covering it with sea-water, l()r it 

 is natural to them to burrow under ground when 

 they change into chrysalides.^ We have seen this 

 caterpillar, as well as that of the brown-eye (Mamcs- 

 ira oil racta), do considerable damage in Wiltshire, 

 but nothing to what is reported ol' it in Germany. 



The leaves of cabbages, cauliflower, brocoli, cole- 

 worls, and turnips, are frequently devoured to a 

 more considerable extent by the sub-gregarious cater- 

 pillars of the white butterflies (PoiUiu brassiccr, P. 

 napij &.C.) From the great multiplicity of the but- 

 terflies, indeed, and from there being two broods in 

 the year, we have reason to wonder that their 

 ravages are not more extensive. l?ut we have re- 

 marked, tiiat they seem more partial to wild than cul- 

 tivated plants ; tor we have seen, near Islington, the 

 oleraceous weeds, such as rape {Brnssica ua/)?'s), 

 over-run with them in the very same fields with cul- 

 tivated cabbages, which were not touched ;t so that 

 the caterpillars are not always so injurious as we 

 might at fust suppose, since in this case they tend to 



* RJsel, Inseckten, i, iv, 170. i J. R. 



