The heat of 144° and 149° destroys them almost | 
immediately, though they can support 140° for 
several hours. If the grains which they inhabit 
have been wet, and exposed to heat, few eels will 
revive after 138°. A vacuum does not prevent 
their resurrection. There are undoubtedly lim- 
its, when, by the lapse of time, the resurgent 
faculty will be lost; but these are yet undefined. 
Mr. Needham carried blighted wheat from Eng- 
land to Portugal, the eels of which revived after 
two years desiccation. Baker recovered them 
after four years: and they are said to have re- 
vived after the extraordinary interval of twenty- 
seven years. 
Leeuwenhoek and Hartsoeker both claim the 
discovery of seminal vermiculi; Haller ascribes 
it to Ludovic Hamma, a young German. On 
presenting the fluid taken warm from an ani- 
mal, to a powerful magnifier, infinite numbers of 
vermiculi are observed swimming with very lively 
motion, and varying their course as fishes do in 
water. Their general figure resembles that of a 
tadpole, excepting that the tail is longer in pro- 
portion, and the body of smaller dimensions. If 
the portion taken for examination is of too thick 
consistency, it may be diluted with saliva, which 
is the only transparent liquid not fatal to the 
vermiculi ; they then become clearly and dis- 
tinctly visible, smaller than the red globules of 
blood. The human fluid being taken from a 
dead body, and presented to the microscope, the 
thermometer standing at 48°, nothing could at 
first be discovered, on account of its opacity. 
When beginning to dissolve, the irregular parts 
seemed in an indistinct slow fermentation ; but, 
on increasing the magnifying power, the motion 
was seen to arise from corpuscula infinitely more 
minute than these parts, of a globular figure, and 
provided with a short filament, or tail: see /vgs. 
lland12. These were the vermiculi, which ex- 
hibited two kinds of motion, one consisting 
merely in oscillation from right to left, and the 
other in progression forward. But they seemed 
insensible of the surrounding objects, and blindly 
rushed against them; or, if involved amidst a 
number of obstacles, they pushed their way 
through the places where they found no resist- 
ance. In twenty-three minutes, their motion, 
which had been incessant, began to decline, and 
in an hour and a half it was almost totally gone. 
The fluid of a ram being put into a watch-glass, 
it appeared to the naked eye in continual agita- 
tion, though situated on an immoveable plane. 
On examination with the microscope, this was 
observed to proceed from innumerable vermiculi 
all in motion, which were larger than the for- 
mer; the body, an oval part, sometimes was im- 
mersed in the fluid, or disappeared, and some- 
times came to the surface. Though the ther- 
mometer was at 77°, they hardly lived an hour. 
Similar vermiculi are found in the prolific fluid 
of all male animals, from those of the largest size 
down to the smallest insect : and naturalists af- 
ANIMALCULE. 
195 
firm, that a general resemblance pervades the 
whole, as the chief difference, except in a few 
examples, consists in the length and slenderness 
of the tail. But the size of the vermiculi does 
not depend on that of the animal, for they are 
found larger in the small ones, than in some of 
greater bulk: neither are they all of equal size 
among themselves, which is particularly evident 
in the fluid of the horse. 
It is said, that these animals are never found 
in males until the age of puberty; that they de- 
crease as life advances, and in old men are alto- 
gether wanting. The like is reported of the in- 
ferior animals ; none could be discovered in very 
young rams; they were more numerous in young 
bulls, two or three years old, than those of five 
or six. They have been unsuccessfully sought 
for in the mule. In the human species, it is also 
said, that they do not appear during the preva- 
lence of the venereal disease. All these facts per- 
haps require corroboration, by a series of more 
careful experiments than, we apprehend, they 
have yet received. 
The use of the vermiculi is yet unknown. No 
sooner were thev discovered, than various con- 
jectures were formed concerning them, and these 
stood on plausible grounds, until overturned by 
more logical reasoning. The most important hy- 
pothesis was that which supposed them the germs 
of future animals; that they were transmitted 
to the female, and expanded into her offspring. 
But such theories have vanished. 
Animalcules are found in the recently voided 
excrements of some animals, and also in the 
stomachs and during the digestion of the rumi- 
nating animals. The number of these animalcules 
is so considerable, that in five centigrammes of 
alimentary matter taken from the first and se- 
cond stomachs of the sheep, for example, MM. 
Gruby and Delafond found from 15 to 20 animal- 
cules of different species and various sizes. In 
the third, and especially in the fourth stomach, 
these animals are dead, and only to be recognised 
by the form of their carapace or transparent en- 
velop, which then appears quite empty; while 
of those animals which possess no carapaces, no 
trace of them can be detected in their stomachs. 
In the small and in the large intestines, we find 
only some fragments of carapaces. Animalcules 
are also found, in great number, in the cecum 
and dilated colon of the horse ; while their empty 
carapaces occur in the contracted colon and rec- 
tum. The conclusion from these facts appears 
to be, that the organic matter of these animals, 
consisting of fibrin and albumen, supplies animal 
matter for digestion even to herbivorous animals ; 
that in the sheep and horse, which take only 
vegetable matters into their stomachs, nearly a 
fifth part of these matters is destined to give 
sustenance to a great number of animals of in- 
ferior development, which, digested in their turn, 
will contribute some animal matter to the gen-= 
eral nutrition of these herbivorous animals. 
a et 
aul Au fithnlesnay 
