220 DISEASES OF INSECTS. 
Was to feed upon; though some appear to pierce it with 
their ovipositor, and consequently introduce their egg 
within : for he says afterwards ; " I have seen with my 
own eyes a certain kind of wild flies deposit their eggs 
upon other eggs, and bore and pierce others with an 
aculeus — by which they have introduced the egg a ." 
Count Zinanni, a correspondent of Reaumur's, saw an 
Ichneumon pierce the eggs with her ovipositor repeat- 
edly; which in about fifteen days were filled with the 
pupa, and in six more produced the imago b . I. Ovu- 
lorum L. is the only known species of egg-devourers ; 
but most likely there are many, varying in size, accord- 
ing to the size of the egg they inhabit. Probably 
I. Atomus L., and /. Punctum Shaw, are of this descrip- 
tion c . It is wonderful what a number these little flies 
destroy : — out of a mass of more than sixty eggs which 
was brought to De Geer, not one had escaped the Ich- 
neumon d . But the most extraordinary thing is, that 
even these little creatures we are told are destroyed by 
another still more minute e . 
Though the animals we are speaking of usually destroy 
only a single egg, yet some appear not so to confine 
themselves. Geoffrey informs us that the larva of one 
of the Ichneumons whose females are without wings 
(Crypius) devours the eggs of the nests of spiders, and 
from its size — it is nearly a quarter of an inch long — 
it must require several of them to bring it to matu- 
rity f . One of those also which destroys the gnat infest- 
ing the wheat {I. inscrens) appears to devour them in 
a Vallisnieri Lettere, &c. 80. b Reanm. vi. 29G — . 
Linne evidently has described another species under /. Ovulorum, 
in Fn. Suec. 1644. d De Geer i. 593—. 
e X. Diet. d'Hist. Nat. vi. 10. « Geoffr. Hist. Ins. Par. ii. 361. 
