214 INSECT TRANSFORMATIONS. 



keep clown the weeds, while the birds and the 

 ichneumon-flies keep them in check by making- prey 

 of them. 



The gregarious caterpillars of an allied species, 

 called the black-veined white butterfly (Pieris Cra- 

 tcBgi, Stephens), is in some seasons and districts 

 no less destructive to orchards and hawthorn hedges 

 than the preceding ones are to the kitchen-garden. 

 Salisbury, who wrote at Chelsea in 1815, says it 

 *' commits great destruction every spring, and not 

 only to the apple-trees, but other kinds of fruits*." 

 Mr. Stephens, writing in 1827, says, " ia June 1810, 

 I saw it in plenty at Coombe Wood, and in the fol- 

 lowing year J captured several at Muswell-hill, since 

 which time I have not seen any at large f." Mr. 

 Haworth also says, " it has not of late years been 

 seen at Chelsea, where it formerly abounded." We 

 have never met \\'\i\\ it at all. According to Salisbury 

 the female butterfly lays her eggs near the extremity 

 of an oid rather than a young branch, and covers 

 them with a coating of gluten, which is both imper- 

 vious to moisture and impenetrable (this we doubt) 

 to the bills of birds. '' In this state," he adds, " we 

 have instances of their remaining without losing their 

 vitality for several years, until a favourable opportu- 

 nity of their being brought into existence arrives |.'* 

 The caterpillars, which are at first black and hairy, 

 live in common in a silken tent. They become sub- 

 sequently striped with reddish brown, and disperse 

 over the trees. This caterpillar and its butterfly are 

 figured in a subsequent page. 



Our gooseberry and red-currant bushes are very 

 fiequently despoiled of their leaves, both by the 

 speckled caterpillar of the magpie-moth (^Ahraxaa 

 grossulariata), and by what Reaumur terms the 



♦ Hints on Orchards, p. 56. f Illustrations, i. Haustellala, 27. 

 X Hints on Orcliards, p. 57. 



i, 



