$26 MR HARDT ON INSECTS 



the margins of the loaves. Some of them commit groat ravages among 

 seeds antl grains, by depositing their eggs in lioles driHed into them with 

 their snout, whence proceed grubs that not only destroy the principle of 

 vegetation, but devour the entire internal substance. None of the species 

 attached to the turnip, so far as has been ascertained^ are chargeable with 

 this habit. One species, the Nedym contractus, I have already mentioned 

 in connection with the turnip beetle, as destructive to the young turnip. 

 It is black, with a bluish tinge on the wing cases ; the head in small, and 

 furnislied with a long, slender, bent snout, which at the insect's will, tits 

 closely to the breast; the second division of its body bears anteriorly two 

 acute projections ; and its shoulders are prominent. It is even more mi- 

 nutu than the turnip beetle, and, as it does not leap, but, on the least dis- 

 turbance, falls to the ground, and pretends to be dead, none of the ex- 

 pedients for catching the insect will avail with it. In cold weather it retires 

 into the soil at the root of the plant. It survives the winter in moss, or at the 

 roots of nettles, on which it likewise feeds. It occurs in the turnip fields in 

 December, and I have found it abundant among grass in February, and it 

 continues on through the following months. The flowers of turnips, and of 

 the wild mustard and radish, are much relished by it, and on them it pairs. 

 It frequents, in like manner, all cruciferous weeds to which the turnip fly is 

 attached. It is one of those insects to which has been ascribed the com- 

 mencement of the disease called fingers-and-toes, anbury or club-root. Mr 

 Kirby bred it, and N. assimilis, a larger greyish-black species, likewise com- 

 mon on the turnip blossom, from the small white maggot in the wen-like 

 galls at the roots of Sinapsis arvensii (Wild Mustard).* The insect bred 

 from turnips infested with flngers-and-toes,j- Avas Nedyns sideicollis, equally 

 common with N. agsimilis, and very similar to it j but differing by being of 

 a deeper black, by its wing cases being more decidedly granulated, by hav- 

 ing its beak and legs shorter, and its thighs stouter, and toothed. Be- 

 sides these three, we have in the turnip fields, N. Boraginis, whose his- 

 tory has not been traced. The irritation occasioned by the larva), it has 

 been conjectured, prevents the turnip from increasing in bulk, and causes 

 the nourishment sent down from the leaves to be expended in the forma- 

 tion of those fantastic growths that characterise the disease, and in which 

 it continues to indulge long after the insect has deserted its nidus. The 

 roots thus affected speedily tend to corruption, become exceedingly fe- 

 tid, and, before the autumn has closed, are infested with various kinds of 

 insects that feed upon decaying substances. J 



The disease in this county manifests itself on moory soils destitute of 

 lime, and on those with a superabundance of vegetable matter. A part of 

 the field much cut up by carting manure will be affected, while the rest will 

 comparatively escape. Lime, in this case, is the grand corrective, probably, 

 by enabling the turnip to outgrow its early injuries. As a proof of this, 

 I have noticed several examples of turnips originally diseased, forming 

 two bulbs one above the other ; which, although small, were quite sound 

 and fleshy internally, and free from stringiness. Mr G. W. Johnson, who 

 has written a paper in the Quarterly Journal of Agriculture on this disease, 

 states that Mr Smith, gardener to M. Bell, Esq. of Wolsington, Northum- 

 berland, found that charcoal dust spread about half-an-inch deep on the 

 surface, prevented its occurrence in the garden. § Soot is equally efficaci- 

 ous. Marl has been recommended ; also brick ash, and paring and burning. 

 Mr Johnson tried salt, but the experiment was not decisive, and has a 

 high opinion of hydrosulphate of lime, which may be procured from the gas- 

 works; which substance, in a dry state, he also thinks, would destroy the 

 turnip tly.[| Soap-boiler's waste, incorporated with the soil, has been used 

 with beneficial effect in the neighbourhood of London. Since its value has 

 been discovered, the price has risen from 6d to 5s per cart-load.^ 



♦ Kirby & Spence, Introduction to Entomology, i,, 186, 418. f Sec note A. 



I See note B. 

 § Quart. Journ. of Agric, viii., 313. Trans, of London Ilort. Soc, vi., art 2. 

 t! Quart. Ji>iun of A^'iic, viii,. 31.5. ^ J. M., Gardeners' Mnija/.iiio, viii . 498. 



