140 INDIRECT INJURIES CAUSED BY INSECTS. 



for the table, their beauty and delicacy are often marred by the trouble- 

 some earwig, which, insinuating itself into them, defiles them with its 

 excrements ; while the seed is often nearly wholly destroyed (as was the 

 case in Suffolk in 1836 and the three following years) by the grubs of a 

 fly (Anthomyia Lactuca Bouche) which live in the involucre, and feed 

 on the seeds and receptacle.^ What more acceptable vegetable in the 

 spring than brocoli? Yet how dreadfully is its foliage often ravaged in 

 the autumn by numerous hordes of the cabbage-butterfly ! so that, in an 

 extensive garden, you will sometimes see nothing left of the leaves except 

 the veins and stalks. — What more useful, again, than the cabbage? Be- 

 sides the same insect, which injures them in a similar way, and a species 

 of field-bug (Pentatoma ornata), which pierces the leaves like a sieve^, in 

 some countries they are infested by the caterpillar of a most destructive 

 moth (Mamestra Brassica), to which I have before alluded ; which, not 

 content with the leaves, penetrates into the very heart of the plant.' — One 

 of the most delicate and admired of all table vegetables, concerning which 

 gardeners are most apt to pride themselves, and bestow much pains to 

 produce in perfection, I mean the cauliflower, is often attacked by a fly, 

 which, ovipositing in that part of the stalk covered by the earth, the 

 maggots, when hatched, occasion the plant to wither and die, or to produce 

 a worthless head.'' Even when the head is good and handsome, if not 

 carefully examined previous to being cooked, it is often rendered disgusting 

 by earwigs that have crept into it, or the green caterpillar of Pontia 

 RapcB. In 1836, as we learn from Mr. Westwood, great injury was done 

 in the market gardens to the west of London to the cauliflowers and other 

 plants of the cabbage tribe by a species of aphis covered with a purple 

 powder, which had not been before observed by the gardeners who called 

 it a new kind of blight.^ 



» Curtis in Gardener's Chronicle, 1841, p, 363. 



* Koliar on his. inj. to Gardeners, ice. p. 148. 



' De Geer, ii. 440. In the summer of 1826 when at Brussels, I observed that delicious 

 vegetable of the cabbage tribe so largely cultivated there under the name of Jets de choux, 

 and which in England we call Brussels sprouts, to be materially injured in the later stages 

 of its growth by the attacks of the turnip-flea, and other little beetles of the same genus 

 {Haltica), which were so numerous and so universally prevalent, that I scarcely ever ex- 

 amined a full-grown plant from which a vast number might not have been collected. 

 Some plants were almost black with them, the species most abundant being of a dark cop- 

 per tinge. They had not merely eroded the cuticle in various parts, so as to give the leaves 

 a brown blistered appearance, but had also eaten them into large holes, at the margin of 

 which I often saw them in the act of gnawing; and the stunted and unhealthy appearance 

 of the plants sufficiently indicated the injurious effect of this interruption of the proper 

 office of the sap. What was particularly remarkable, considering the locomotive powers of 

 these insects, was that the young turnips, sown in August after the wheat and rye, close to 

 acres of Brussels sprouts (which all round Brussels are planted in the open fields among 

 other crops), infested by myriads of these insects, were not more eaten by them than they 

 usually are in England, and produced good average crops. It would seem, agreeably to a 

 fact which I shall mention in its place in speaking of the food of insects, that they prefer 

 the taste of leaves to which they have been accustomed, to younger plants of the same 

 natural family ; and hence perhaps the previous sowing of a crop of cabbage-plants in the 

 corner of a field meant for turnips, might allure and keep there the great bulk of these 

 insects present in the vicinity, until the turnips were out of danger. 



* Perhaps this fly is the same which Linne confounded with Tachina Larvarum, which 

 he says he had found in the roots of the cabbage ( Syst. Nat. 992. 78.) I say " confounded," 

 because it is not likely that the same species should be parasitic in an insect, and also inha- 

 bit a vegetable. It is obviously the same described by Koliar from Bouche under the name 

 of Anthomyia Brassicce (159), which he states often destroys whole fields of cabbages by 

 boring into the roots and stalks. 



* !ZV«B«. Ent, Soc. Lond. ii. proc. xxi. 



