affecting the Turnips, Corn-crops, ^-c. 
189 
might not be found, and but few crops that they will not attack : 
but some situations are more favourable to their increase than 
others, and there are particular vegetables to which they un- 
doubtedly give a preference. This may, however, in some mea- 
sure arise from the larvae of the different species not having 
exactly the same tastes, and we have already shown that Wire- 
worms, the offspring of three, if not four, distinct species of 
Elaters, attack the crops ; vet some of them are so similar, except 
in size, that at present no tangible characters have been discovered 
to distinguish one from another ; moreover all root-worms are 
called Wirew(nms by the fanner; but in this matter we hope to 
set him right, by giving descriptions and figures of the false 
Wireworms before we close the subject. At present they are 
accused of attacking wheat, rye, barley, oats, grass, turnips, rape, 
cabbages, potatoes, mangold-wurzel, carrots, onions, lettuces, 
hops, irises, carnations, pinks, dahlias, lobelias, and a variety of 
garden flowers ; but in many instances the insects sent to me as 
the offenders were not the offspring of the Elaters, and conse- 
quently were not true Wireworms, but the larva? of Crane-flies 
and other dipterous or two-winged flies, also the Juli or Mille- 
pedes, Centipedes, &c. 
If it be correct, and there seems to be no reason to doubt the 
statement,* that a Wireworm is feeding five years in the earth, it is 
evident from the variety of sizes one discovers of them at the same 
period and about the same turnip-root, for instance, that there 
must be a great difference in their ages, and possibly two kinds ; 
and as they will not voluntarily leave the field in which they were 
hatched until they have arrived at their perfect state and become 
Elaters, it is impossible by any change of crops to remedy the evil, 
unless indeed one could discover some vegetable which they abso- 
lutely disliked ; or by ploughing, harrowing, and keeping the soil 
perfectly free from weeds or plants of every kind, especially the 
grasses, they might be starved out. Whether they can fast for a 
long period is very doubtful I think, although Bierkander favours 
such an opinion, for it is principally in their perfect state that 
insects can live without food for an extraordinary space of time. 
Some importance, however, must be attached to the generally- 
received opinion that it is in all probability whilst the surface of 
the field is undisturbed that the eggs are deposited, consequently 
the crops that follow fallows, or pasture-land when broken up, 
are most likely to fall a sacrifice, and that for several succeeding 
years; and it is the same with a clover layer; whereas during 
turnips, potatoes, and similar crops, no eggs or very few are laid 
* Bierkander kept them living on roots of corn five years, and those which 
I have had feeding for ten or twelve months scarcely increased in size 
during the time. 
