94 
MANGOLDS. 
exercising their cannibal propensities by feeding on each other, as 
there were broken remains of skin of other Silplia maggots in the box. 
At this date, on examining some of the specimens previously sent me, 
I found they were looking in extremely good health, and of a bright 
shiny black, and, as the Beet-leaves enclosed with them were faded, 
and I usually found some of the grubs under, or by the portion of a 
chicken’s leg which had become partially putrid, I conjectured that— 
as they had no longer Beet- or Mangold-leaves in a state suitable 
for food—they were feeding instead on the putrid meat (or 
“ carrion ” from which they take a part of their name. Five 
days later one or two of the grubs were dead, but others, which 
were not observable until I stirred the soil, were lively and apparently 
thriving. 
The following notes, also by Mr. D. Sym Scott, convey information 
regarding the time of attack,—namely, that it is chiefly carried on at 
night, and the plant-feeder consequently not at once observable ; also 
that the later-sown Mangolds were not so badly injured as the others, 
by reason of the grubs being at that time nearer the date of their 
change to chrysalis state ; and also full notes are given of the method 
in which the grub attacks leafage. 
As we were not fully informed on these points, I requested 
information on them from Mr. Sym Scott, as a well-skilled and long- 
accustomed observer, and in reply he favoured me with the following 
useful notes :— 
“ With regard to injury done to Mangold-crop by larvae of Silplia 
opaca , several farmers in this locality have suffered, myself among 
them. For some time I could not make out what was wrong with the 
plant, and (with others) blamed frost at night; but one morning 
before the dew was off I detected the insect at work, and reported this 
to others, who also found them. This confirmed my suspicion about 
an insect, and I also saw that the insect fed only during the night , or 
ivlieyi the leaves were moist; when the sun was up strongly they buried 
at or near the root of the plant, which accounted for my not seeing 
cause of failure sooner. The attack only affected the early sown, 
which leads me to believe if we do not sow till May, the season of 
attack will be over before the plant appears above ground. It was on 
the most sheltered side of my field the attack was most severe. On 
this side of the field the crop is ruined, but on the more exposed part 
the plants are recovering. 
“ No bone or any artificial fertilizer were used, either here or 
elsewhere, in this part, nor have any been used for years past, so that 
bone manure is not the cause. I use only farmyard, and that of good 
quality, same as used for years. I have further to say that the soil 
on the different farms is in each instance different; the treatment here 
