192 



TURNIPS. 



2)revious cultivation suited to push on growth of tlie plant, — 

 treatment at time of sowing, — and measures of tried practical 

 service for clearing the pest when on the plants. Other 

 minor points of more or less service, such as mixtures of 

 different ages or different kinds of seed, — the very doubtful 

 benefit of steeps, — plans found in some cases of use for 

 mechanically catching the fly, &c., space does not allow of 

 insertion here. 



Much of serviceable interest was also given, regarding 

 extent and nature of attack and details of damage in the in- 

 fested area ; and I was particularly indebted to Mr. J. H. 

 Arkwright, of Hampton Court, Leominster, for the valuable 

 mass of information which he placed in my hands, containing 

 details of methods of cultivation, amount of attack, and 

 means of prevention and remedy used in Herefordshire, and 

 more especially from parishes lying in a district of a radius 

 of seven miles round Leominster ; much also was given me 

 by many other valued contributors, to all of whom I still feel 

 my sincere acknowledgments to be especially due, as forming 

 my Turnip Fly Eeport was one of my first pieces of public 

 work, and the usefulness was entirely owing to the widespread 

 and skilled contributions and co-operation so kindly granted 

 me. — Ed. 



Diamond-back Moth. 



Plutella cruciferamm, Zell. ; Cerostoma xylostella, Curtis. 



|^>i;l.,, J^ X 



1, caterpillar ; 2, eggs ; 3 — 5, Diamond-back Moth, nat. size and mag. 



The appearance of the Diamond-back Moth caterpillar on 

 the Turnip crops has only been recorded (with us) now and 

 then, but when it does happen it is often very destructive. 

 The caterpillars feed voraciously, in bad attack clearing away 

 the substance of the leaves down to the ribs, and sometimes 

 gnawing away these also. 



In 1851 this caterpillar is recorded as having appeared in 



