GENERATIVE ORGANS OF SOME CARTILAGINOUS FISHES. 501 
as were also the uterine cavities. A little fluid lubricating the latter was scraped 
off and subjected to the microscope; some blood corpuscles were seen in it, and 
minute globules, and also two spermatozoa, respecting which it is said in my notes, 
“I think there can be no mistake, their form being so peculiar.” 
6. Of the Raia Aquila.—Of this fish I have notes of two specimens only, both 
procured in Malta, and both females. 
The first was procured on the 12th April. In each of its oviducts was a large 
membranous shell, which, independent of its horns, was about five inches long. 
One of them, opened, was found to contain a yolk about the size of the yolk of a 
hen’s egg; a considerable quantity of glairy white enveloped it. The shell exter- 
nally was nearly black—rough, tough, and very strong: internally it was lined 
with a delicate white glistening membrane. Above that part of the oviduct in 
which the egg was contained was a large globular body surrounding the duct, in 
appearance, as to structure, more like a testis than any other that at the instant 
IT could call to mind. The lower end of the oviduct terminated in the cloaca; it 
was so contracted, that the little finger was introduced with difficulty. There 
was no appearance of development in the ova. 
The second fish was obtained on the 22d September. Though quite fresh, its 
ovaries and oviducts were for most part reduced to a pulp, as if by a process like 
that which sometimes destroys the stomach, and has been referred to the action 
of the gastric juice. In this instance, however, the stomach was quite sound, 
without any traces of softening. It was of moderate size, full of broken food, 
suggesting the idea that this fish masticates its food, for which its strong, ]ami- 
nated molar teeth are so well adapted. 
7. Of the Squalus Canicula.—Of this species I have notes of four, one of them 
amale. All were procured in Malta. 
I shall first make mention of the male. It was obtained on the 11th Sep- 
tember. Its anal appendages are merely stated to be similar in structure to those 
of the torpedo, the lateral anal fins uniting behind them and partly. covering them. 
_ The testes were very distinct, and situated high up in the abdominal cavity; the 
spermatic tubes large and tortuous, terminating in vesiculee seminales, and these 
in a single papilla situated in the cloaca, close to the anus. When the vesicule 
were pressed, a thick, creamy fluid was discharged, flowing from the papilla. 
Of the other fishes, females, the first was obtained on the 22d April. A 
large cluster of eggs was situated over the spine: these of various sizes—the 
largest about the size of large cherries; their membrane was vascular, including 
ayolk. The upper part of each oviduct was also very vascular. The infundi- 
bulum was small. In the oviduct there were no ova and no enlargement. Each 
was provided with a glandular structure. Below the gland, where it is presumed 
the egg would rest and acquire its shell, the oviduct was very small and pale— 
not thicker than a crow quill—its sides in contact. 
