PHYSIOLOGY. 
the reader will find under the articles Ana- 
tomy, Comparative Anatomy^ and F(E- 
TCS. 
The bodies of the male and female pre- 
sent very obvious differences in appearance 
and character, which have been ascribed to 
the influence of the generative organs upon 
the constitution. The removal of the testes 
in the male, prevents those changes in the 
beard and voice, at the time of puberty, 
which would otherwise occur ; and eunuchs 
even approach in other respects to the fe- 
male character, as in the breadth and pro- 
jection of the hips. Again, in some remark- 
able cases, where the organs of the female 
have been wanting, or mal-formed, similar 
effects have taken place in the constitu- 
tion ; so that there is some reason for say- 
ing with Van Helmont, propter solum ute- 
rum mulier est, id quod est. 
Hertnaphrodism, or the union of both 
sexes in the same individual, is impossible 
in man and the warm-blooded animals. All 
the supposed hermaphrodites hitherto ex- 
amined were mal-formed beings, whose 
male organs were imperfect, or the female 
apparatus too prominent, so as to render 
the sex doubtful. No one has shown him- 
self capable of impregnating his own per- 
son, so as to produce a being like himself ; 
indeed, in most instances they were incapa- 
ble of assisting in reproduction, as an im- 
perfection of the organs employed for that 
purpose condemned them to sterility. 
Man presents a peculiarity, in not being 
subject to the influence of the seasons in 
the exercise of his generative functions; 
while other animals cohabit at fixed periods 
and certain times of the year, and after- 
wards seem to forget the pleasures of love 
to satisfy other wants. 
Conception. Physiologists have not hi- 
therso succeeded in explaining the mecha- 
nism of that elongated and distended state 
of the penis, occurring under the irritation 
of the sexual passion, which adapts the or- 
gan to the performance of its natural func- 
tions. The obvious circumstances are, that 
the cells of the corpus spongiosum urethrae, 
and corpora cavernosa penis, are distended 
to the utmost with blood, poured into them 
from the arteries much faster than it can 
be, or at least is returned by the veins. The 
irritation, which affects the penis, extends 
to the internal parts. The secretion of the 
testes becomes more active, and these bo- 
dies are drawn up towards the abdomen ; 
the vesiculae seminales, and the ducts of the 
prostate, also pour out their .contents into 
the urethra. The semen is a mixed fluid> 
derived from the three sources just men- 
tioned ; but the smallest part probably 
comes from the testes. The most remark- 
able circumstance in this fluid is, that it 
contains numerous microscopic animalcula, 
with a round head and slender tail, moving 
about with rapidity. 
The prolific liquor is expelled from the 
penis by a spasmodic action of the accele- 
rator urinte muscle : the whole body seems 
to participate in the same convulsive state, 
and the instant of ejaculation is marked by 
an orgasm through every part. It seems 
tliat nature has forgotten, for the moment, 
every other function, and is totally occu- 
pied in collecting her powers, and directing 
them towards the same point. Hence an 
universal languor follows this general con- 
vulsion, and hence the old observation, 
omne animal post coitum triste: 
The seminal liquor, thus propelled into the 
generative organs of the female, is supposed 
to pass through the uterus and fallopian tubes, 
and to come into actual contact with the 
ovaria. The closeness of the mouth, and 
indeed of the whole cavity of the uterus, 
together with the very small calibre of the 
fallopian tube, especially at its origin in the 
uterus, (where it will only admit a bristle) 
are difficulties in the way of this explana- 
tion, which have led to the opinion, that 
the semen itself does not penetrate into the 
uterus, but tliat an exhalation, or aura semu 
nalis, comes into contact with the germs, 
and is sufficient for their fecundation. Ibis 
is opposed by the experiments of Spallan- 
zani and others, in which the ova of frogs 
were readily impregnated by contact of the 
seminal fluid, but were not at all affected 
by the vapour or aura. 
The attachment of the fimbriae of the 
tube to the ovarium, which experiment has 
shown to occur during coition, establishes 
an uninterrupted canal from the Uterus to 
the ovarium, and prevents the semen from 
becoming diffused in the abdomen. 
The germ of the future being pre-exists 
in the ovarium, where it is formed by a pe- 
culiar action of the part, in short, by a true 
secretion. This germ, in its original state, 
is a small vesicle of fluid, first noticed by 
De Graaf, whence the term of ovula Graaf- 
iana, applied to their appearance in the vir- 
gin ovary. Here we do not mean to coun- 
tenance those doctrines of evolution which 
suppose, that generation only developes 
germs that have existed from the beginning 
of the world. We suppose, that the ora 
