REVIEW. 528 
that it is effected in a few moments, and that in the case of the giraffe, also, 
no peculiar position is necessary. 
“ This gentleman has satisfied himself that in many animals one sexual 
congress suffices for the perfect fecundation of the female. I believe the 
mare is not unfrequently put by ; and if she will allow the stallion to mount 
a second time, an hour or two after the first mount, a second copulation 
takes place ; but this is done rather as a matter of precaution to ensure a 
foal, than otherwise.” 
Under the head of emission, the author enters at large into 
the immediate cause of ejaculation, the influence which 
semen exerts on the system, and the effects of castration as 
witnessed in animals. In speaking of the influence of age in 
changing the secretion, he says : 
“Experience proves that old age cannot support the drain, and the sub- 
sequent nervous depression arising from ejaculation. Secretion is not ab- 
solutely stopped by bountiful nature ; but semen is formed slowly, and 
with effort, and may remain for a long time pent up in the canals which 
have secreted it. Professed breeders of animals refuse to rear the pro- 
duce of old sires or dams, and I am told they recognise this class of 
young stock by several marks, as for instance the deeper hollows over 
the eyes, and by the sunken eye itself. So well are these facts known to 
horse-dealers, that they refuse to purchase young horses presenting these 
appearances, being convinced that they will not stand work, or turn out 
well. I am not aware that we possess descriptions of old men’s children, 
but as far as my experience goes, they are not promising. If it is true, 
as is now generally admitted, that from the moment of conception of 
the individual the duration of existence is, to a certain extent, prede- 
termined, in consequence of the organization which he has received, I think 
it follows that one human being born of a rich stock of force and vitality 
will take a greater number of years to arrive at the culmination and the 
term of his existence, than another born under opposite conditions (even 
more favorable as far as worldly externals are concerned.)” 
At page 69 the effect of excesses on the human being are 
exemplified, and we would ask if similar consequences may 
not be expected in entire horses, as we believe that many 
of the disappointments in finding mares barren may 
arise from the agriculturalist taxing the powers of his entire 
horse too much, or allowing an old stallion to cover too many 
mares. Would it not be well for each owner of stallions to 
