M Mv Frev (Kst and ’ Sj^jermnlk SWI 
The next memoir, on the Spernuitic Aihouilcuie^s of different 
animals, by MM. Preyost and Dumas, confirms the very sin- 
gular facts discovered nearly a century and a half ago, by Leu- 
wenhoeck and others, and more lecently investigated by ' Spal- 
lanzani. The design of the authors is, to give a comparative 
description of these animalcules ; and, more especially, to prove 
that they are the result of a real secretion. The rabbit, guinea- 
pig, hedgelfog, cat, dog, horse, rain, goat, and mouse, were the 
animals selected from the mammalia. They were first killed by 
dividing the carotid artery, and an examination was then imme- 
diately made of the fluid contaiiied in the testicles, and in other 
organs wJiich communicate with the urethra, as the vesiculse 
seminales, the prostate, and Cowper’s glands. The three last 
organs do not exist in ail animals, but the testicle is always pre- 
sent, and seems to be the only organ essential to the formatioLt 
of the seminal secretion. On examining these several organs, the 
authors found the fluid of the testicle, and of its epididymis and 
vas deferens, to contain numerous animalcules, the various forms 
and sizes of which, in different animals, they have described and 
delineated in their memoir. Though animalcules were some- 
times found in the vesiculse seminales, it seemed entirely acciden- 
tal, and they regard the testicle as the only secreting organ in 
which these minute beings are formed. The prostate, and the 
glands of Cowper, in particular, never contained animalcules. 
Whatsoever be the nature of these beings, their identity in each 
species of animal, their appearance at the develbpement, and 
through the active condition of the genital organs, and their 
absence in sterile males, seem to shew that they are the result of 
a true secretory function, and the active agents in all fecunda- 
tion. 
In birds, and in animals with cold blood, the genital organs 
consist only of the testicles, and their excretory ducts. In the 
seminal fluid of the common cock, the authors found an im- 
mense number of animalculse, and in that also of the drake and 
sparrow. 
Among reptiles, the viper, frog, and salamander were exa- 
mined, and innumerable animalculae were found in the seminal 
fluid of each. The seminal fluid of different species of snails 
and slugs afforded similar resiilts^ 
