154 INDIEECT INJURIES CAUSED BY INSECTS. 



The caterpillar of the cabbage-butterfly {Pontia Brassicce) is 

 also sometimes found upon the turnip in great numbers ; and 

 Sir Joseph Banks informs me that forty or fifty of the insects 

 before mentioned, called by Mr. Walford the wire-worm, but 

 more probably, as there observed, the larvae of one of the tribe 

 of Brachyptera or love-beetles, have been discovered in Oc- 

 tober just below the leaves in a single bulb of this plant. — - 

 The small knob or tubercle often observable on these roots is 

 inhabited by a grub, which resembles one found in similar 

 knobs on the roots of Sinapis arvensis (from which I have 

 bred Nedyus contractus and N. assimilis^ small weevils nearly 

 related to each other), and like it produces a small weevil, 

 Ceutorhynchus sulcicollis. This, however, does not seem to 

 aifect their growth. Grreat mischief is occasionally done to 

 the young plants by the wire-worm. I was shown a field 

 last summer in which they had destroyed one-fourth of the 

 crop, and the gentleman who showed them to me calculated 

 that his loss by them would be lOOZ. One year he sowed a 

 field thrice with turnips, which were twice wholly, and the 

 third time in great part, cut off by this insect.^ The roots are 

 also sometimes seriously injured by the caterpillars of the moth 

 {.Agrotis Segetum) before mentioned, as destructive to wheat 

 crops on the Continent. Whether the disease to which 

 turnips are subject, in some parts of the kingdom, from the 

 form of the excrescences into Avhich the bulb shoots, called 

 fingers and toes, be occasioned by insects, is not certainly 

 known.^ Another root, the Beet, which has within the last 



insect, and on the turnip-flea in Journal of the Royal Agricultural Society of Eng- 

 land, vol. ii. by John Curtis, Esq. 



1 Trans. Ent. Soc. Land. ii. proc. xxx. A striking instance of the use of 

 hand-picking (in most cases by far the most effective mode of getting rid of 

 insects) appeared in the West Briton, a provincial paper, in November, 1838, 

 stating that Mr. G. Pearce of Pennare Goran had saved an acre and a half of 

 turnips, sown to replace wheat destroyed by the wire-worm and attacked by 

 hosts of these larvae, by setting boys to collect them, who, at the rate of three 

 half pence per 100, gathered 18,000, as many as 50 having been taken from one 

 turnip. Thus at an expence of only \l. 2s. 6d. an acre and a half of turnips, 

 worth from 51. to 71. or more, was saved ; while as the boys could each collect 

 600 per day, 30 days' employment was given to them at 9c?. per day, which they 

 would not otherwise have had. 



2 Spence's Observations on the Disease in Turnips called Fingers and Toes, 

 Hull, 1812. 8vo. 



