190 INDIRECT INJURIES CAUSED BY INSECTS. 



One of the most delicate and admired of all table vege- 

 tables, concerning which gardeners are most apt to pride 

 themselves, and bestow much pains to produce in per- 

 fection, 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 a . 

 Even when the head is good and handsome, if not care- 

 fully examined previous to being cooked, it is often ren- 



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 uni- 

 versally prevalent, that I scarcely ever examined 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 aeneous tinge. They had not merely eroded the cuticle 

 in various parts, so as to give the leaves a brown blistered appear- 

 ance, 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 inju- 

 rious 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 already mentioned, (see Vol. I. 4th Edit. 

 p. 389,) 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 

 inhabit a vegetable. 



