affecting the Com- Crops. 
143 
upon a moderate calculation, more than half of the grain would 
be destroyed. I have noticed twelve at one time depositing their 
eggs in the same ear. It is remarkable that amongst the myriads 
that I have seen of the female, I should not have observed one 
which I could take for the male ; indeed, towards the latter end 
of the month I took two or three specimens, which, except 
that they had black bodies and were smaller, appeared exactly 
similar to our Tipula ; but as neither their antennae are hairy, 
nor their wings spotted, as was the case with the specimen you 
received from Mr. Markwick, they can scarcely be the male. 
Indeed the appearance of the male, instead of being later than that 
of the female, ought to be as early or earlier, in order that they 
may be in readiness to perform the work of impregnation previous 
to the season in which the females lay their eggs, which begins, at 
least it did this year, with the month of June. Hence I suppose 
that each sex is disclosed from the pupa in the genial month of 
May. 
" Although these insects are so numerous in the evening, yet 
in the morning not a single one is to be seen upon the wing : they 
do not, however, then quit the field which is the scene of their 
employment; for, upon shaking the stalks of the wheat, or other- 
wise disturbing them, they will fly about near the ground in great 
numbers. I found their station of repose to be upon the lower 
part of the culm, with their heads upwards. 
" It is very entertaining to observe the method to which these 
insects have recourse in order to deposit their eggs in a situation 
where the larva; may soon arrive at their food : when engaged in 
this employment they are not soon disturbed; which circumstance 
affords the observer an excellent opportunity of examination. As 
I hinted before, a number may be seen at the same time upon one 
ear : they place themselves in such a position that their anus stands 
nearly at right angles with the margin of the glume of that floret 
which they mean to pierce. But how are they to introduce their 
eggs within the floret, for they deposit them between the exterior 
and interior valvules of the corolla ? To look at them when they 
are not engaged in this employment, their anus appears to be 
furnished with no instrument adapted to so nice an operation ; but 
upon pressure it exerts a long retractile tube or vagina, which 
unsheaths an aculeus (if I may so term it) as fine as a hair and 
very long (fig. 8 r). This aculeus it introduces into the floret, 
and there deposits its eggs, which it usually places upon the in- 
terior valvule of the corolla, just above the stigmata. After she 
has done laying her eggs, the insect withdraws her aculeus with 
great caution and deliberation : yet it sometimes happens that she 
is unable to etlect this ; in which case she is detained a prisoner 
until some enemy devour her. In this situation I have found 
