DIPTERA. — (&STRIDA. 5717 
animal which is best adapted for the welfare of its progeny, that is, 
in places either where the larva, when hatched, may burrow into the 
back, or other part of the body, or where the larve may be re- 
moved by the tongue of the animal itself into its mouth, and thence 
to the stomach ; in which, exposed to a temperature of more than 100 
degrees of Fahrenheit, they remain until full grown, when in either 
case they quit the body, and making their way to the earth, un- 
dergo their transformations under ground. The ox, horse, ass, rein- 
deer, stag, antelope, camel, sheep, hare, and rhinoceros *, are the only 
quadrupeds hitherto observed to be subject to the attacks of these 
insects, which appear to instil, as their name implies, a surprising 
degree of dread + amongst these animals whenever they make their 
appearance. The larve exhibit three principal variations in their habits, 
being either cutaneous, when the grubs (commonly called Wornils, 
Wormals, or Worbles) reside in tumours beneath the skin of the 
animal attacked ; cervical, when the grubs burrow into the maxillary 
and frontal sinuses through the nostrils ; or gastric, when the grubs, 
called in this case bots, are introduced into the stomach. It would 
seem, however, that these insects occasionally extend their attacks even 
to man; Humboldt having observed some of the South American 
Indians whose abdomen was covered with small tumours, produced, as 
was supposed, by the larva of some Cistrus. Moreover larve, ap- 
parently belonging to this family, have been extracted from the maxil- 
lary and frontal sinuses of the human body. (Latreille, R. An. v. 502.) 
For further notices upon the occurrence of larvae of this family in 
the human body, I must refer to a Memoir by Say, in the Zransac- 
tions of the Acad. of Natural Science. Philadelph. vol. ii., and Bull. 
Scienc. Nat., 1823, part 8., in which is contained the description of a 
* An Cistrideous larva, obtained from the body of a rhinoceros, is contained in 
the Museum of the College of Surgeons. The imago is not known. Can it be the 
Zimb? M. Rob. Desyoidy has communicated to the Academie des Sciences a 
notice of the occurrence of one of these insects in a badger (Comptes Rendus, 1836, 
No. 2.); and M. Vallot, their existence in the bodies of monkies. (See the memoir 
of M. Saint Hilaire, noticed above.) M. V. Audouin has shown me the larva of 
an (Estrus which infests Antilope redunca, which is remarkable for having some of 
the central segments of the body furnished with very large fleshy tubercles; like- 
wise the larva of another exotic species, which, instead of the ordinary double row 
of reflexed points, is entirely covered with minute horny acute tubercles, the sides 
of which, when magnified, are found to be serrated. > 
+ See p. 540. anté, for a notice of the controversy between Messrs. B. Clark and 
MacLeay, relative to the oierpog of the ancients, 
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