PISCES. 
ovary is distinct from the oviduct, as in the 
three higher classes of Vertebrata. When the 
ovules are not developed,* the ovary of the 
Sharks forms a thick. oval lamina slightly 
notched or concave upon its inner border, sus- 
pended upon each side of the vertebral column 
at the very anterior extremity of the abdominal 
cavity, from which point it is prolonged back- 
wards for a greater or less extent. The inferior 
and internal surface of this lamina, that by 
which the ovaria would touch each other if 
approximated, presents no prominences, but is 
of a uniform milk-white colour. The posterior 
surface of the organ has the same appearance, 
Fig. 538. 
Viscera of female Shark, after Hunter. 
a, skin; 56, cut pectoral and pelvic arches; c, heart; h, 
cecal appendage to intestine; m, ovary; g, oviduct ; 7, ute- 
rine portion of oviduct ; s, s, termination of oviducts in clo- 
acal cavity ; ¢, papilla on which the ureters open. 
* Cuvier, Legons d’Anatomie Comparée, tom.viii. 1846. 
VOL, IIl. 
1009 
except that upon the anterior half or two-thirds 
of the ovary little rounded eminences of dif- 
ferent sizes are perceptible, the smallest of 
which are pearl-white, while the larger are of 
an opaque-yellow colour; these are the ovules 
in process of developement from the proligerous 
stratum of the ovary, which gradually increase 
in size as they advance towards maturity, and 
roject through the upper surface of the ovary. 
his latter expands itself in the form of a cap- 
sule over the ovules in such a manner that as 
their developement increases they become de- 
tached from each other, and separating them- 
selves more and more become atlength racemose. 
The remainder of the ovarian lamina 
retains its soft, milky, homogeneous ap- 
pearance, which is very characteristic, 
and resembles very closely one portion 
of the testis of the male. 
In many of the viviparous Sharks, 
that portion of the ovary only which does 
not form eggs is met with upon one 
(generally the left) side of the body, 
whilst upon the opposite the organ 
attains its full developement. 
The general disposition of the rest 
of the generative apparatus is well shewn 
in the accompanying figure (fig. 538) of 
the sexual organs of the female Dog-fish, 
(Spinax acanthias, Cuv.,) taken from 
one of the admirable drawings left by 
John Hunter, and engraved in the Cata- 
logue of the Hunterian Museum. 
The ovary (n) presents ovisacs in dif- 
ferent stages of developement attached 
by a duplicature of peritoneum to the 
side of the spine, immediately below the 
liver and esophagus. The anterior orifi- 
ces of the oviducts (g,q) are situated 
close together above the liver; their 
coats, which are at first thin and mem- 
branous, gradually increase in thickness, 
and about four inches from the orifice 
become suddenly thickened by the addi- 
tion of a laminated glandular structure ; 
this is, however, much less developed in 
the present viviparous species than in 
the oviparous cartilaginous Fishes, and 
the size of the oviduct continued from 
the glandular part more nearly corre- 
sponds with that of the preceding por- 
tion than in the oviparous races. Be- 
yond the glandular portion the oviduct 
gradually increases in diameter, having 
its lining membrane thrown into longi- 
tudinal plice, until suddenly it dilates 
into a wide uterine aa (r), in which, 
in the viviparous Sharks, the young are 
retained after the eggs are hatched, until 
they are fit for exclusion in a living 
state. 
In the dilated uterine portion the 
lining membrane is gathered in close 
longitudinal folds, and their free mar- 
gins, which are beautifully wavy, contain 
each a vessel, which follows the sinuosi- 
ties of the fold, and sends off branches 
to the parietes of the oviduct. To- 
wards the terminations of the oviducts 
3 T 
