affect inf) the Turni2)-Cro2)s. 
123 
pudding (fig. 21), which seemed to be the worst affected, .is the 
taj)-i()ot was generally com})letcly rotten in the earth (fig. 24) : 
the odour was most offensive ; and on opening tlie wet and carious 
parts there were numbers of maggots in groups of five or six 
together, completely imbedded in the putrescent substance 
(fig. 25). I sometimes found as many as twenty in one root. I 
observed with them some minute Acari, both red and whitish, 
with quantities of small rove-beetles with their larvae, and a few 
large carnivorous beetles. The branching roots were covered with 
simple or granulated excrescences (figs. 22 and 23), but thei/ were 
not decaying. The Scotch yellow turnips had grown to a good 
size ; but the tap-root frequently produced a tumour as large as 
a pullet's egg. On cutting them open I found them solid, and, with 
the exception of a few small holes eaten here and there, which 
were like the erosions of the wire-worm, of which I detected one, 
they did not exhibit the slightest signs of any insects inhabiting 
them, even in an embryo state : the centre of the tumours was dis- 
coloured, and the texture perfectly fibrous or woody. The swedes, 
as well as the round white turnips, were but slightly affected. I 
likewise remember examining in August, 1841, at least a dozen 
young cabbage-plants with clubbed roots as large as a child's fist, 
but could not find a single maggot anywhere, and the tumours 
were sound and solid. 
I think from the above evidence it is pretty clear that certain 
conditions of the soil, induced probably by the repetition of cer- 
tain crops, and not insects, are the cause of anbury:* the en- 
largement of the lateral roots, which become woody, stops the 
flow of sap to the bulb ; it consequently ceases to draw nourish- 
ment from the soil, when it dies and rots in the earth, and be- 
comes a fit nidus for a variety of insects. With regard to fingers 
and toes, if that disease be the malformation I take it for, it 
arises possibly from the land not having been sufficiently pre- 
pared for the turnip crop ; but this is an opinion which I venture 
with great deference to offer for the consideration of the practical 
cultivator. 
It will now be necessary to give the histories of the insects 
alluded to which inhabit the anbury. The most important of 
them is the maggot of a delicate gnat, which, as I have already 
stated, lives in small families in the putrid and moist portions of 
the bulb (fig. 25). These larva; are slender, cylindrical, shining, 
and pale yellow (fig. 26) : they taper gradually to the head, which 
* If cabbages be planted, or the seed sown, for several years following, 
upon the same land, the roots get knotty, and the heads become smaller ; 
but if cultivators would procure strong and healthy plants from a market- 
garden, instead of sowing their own seed, it would do much towards obviating 
this mischievous disease. 
