92 STATES OF INSECTS. (Egg.) 
moist situation in which the workers are always careful 
to keep them. By an accurate admeasurement he found 
that those nearly ready to be hatched were almost twice 
as big as those just laid*. A similar observation was 
made on the red eggs of a water-mite (Hydrachna abs- 
tergens) by Rosel, who conjectured that they draw their 
means of increase from the body of the water-scorpions 
(Nepe), of which they form so singular an appendage®, 
which opinion is confirmed by De Geer, who observes 
that when the water-scorpions are covered by an unusual 
number of the eggs of the water-mites, they grow weak 
and languid, and endeavour to rid themselves of their 
parasitic appendages‘. It is most probable that the mite 
lately named (Uropoda vegetans), which is often found 
planted as it were upon the bodies of various beetles, by 
means of a long pedicle, through which, as the foetus by 
an umbilical chord and placenta, it derives its nutriment 
from the above animals, is at first so fixed in the egg 
state, though before it is disengaged from the pedicle it 
is hatched, since it is often found with its legs displayed 
and quite active—this is the more probable, as the eggs 
of the water-mite are fixed by a pedicle to the animals to 
which they are attached4. I have met with a remarkable 
instance, in which pedunculated eggs seem to draw nu- 
triment from the mother, which brings the pedicle still 
nearer to the nature of the umbilical chord. Those of the 
small hemipterous insect which infests the larch before 
alluded to, are attached to the anal end of the mother by 
a short footstalk not longer than the egg. 
Dr. Derham seems to have observed, that the eggs of 
some Diptera, of the tribe of Tipularia, also increase in 
* Fourmis, 69—. > Rosel iti. 152. © De Geer vii. 145. 
* Ibid. 123—. See above, Vou. I. p. 392—. 
