296 M. Krohn on the Anatomy and 
kept in the same vessel, I rarely remarked that they devoured 
one another, or that they were inclined to do so. 
The ovaries have been already described by MM. Quoy and 
Gaimard. Each ovary is a pouch terminated anteriorly m a cecum, 
and fixed by a slender ligament to the inferior wall of the cavity 
of the trunk; it extends in a straight line from anteriorly back- 
wards, parallel to the corresponding margin of the inferior mus- 
cular band, and lastly forms a loop, on rising towards the dorsal 
surface of the animal. There it opens exteriorly between the 
upper muscular band and the base of the last fin. I fancied that 
I perceived in the sides of the ovarian pouch, under a strong 
magnifier, thin fibres, which, where the germs of ova (stroma) 
occurred, appeared to form two interlaced layers. The stroma, 
which may be detected throughout the whole length of each ova- 
rian pouch, only exists im the half of this organ, in relation with 
the ligament. 
The length and the width of the ovaries, very variable accord- 
ing to the age of the individuals, are in direct relation, as may 
easily be conceived, to the number and development of the eggs 
contained in them. In individuals of two lines and a half in 
length, only feeble rudiments of them are seen; the ovules are 
then extremely small. These ovaries increase more and more im 
length and breadth up to the adult age, that is to say, up to the 
moment of coition, at which period they are seen to project 
above the first pair of fins*. All the eggs, the smallest as well 
as the largest, exhibit a germinal vesicle; but no circumscribed 
germinal spot can be discovered in them. The vesicle appears of 
a relatively very considerable volume in the youngest ovules ; it 
increases at first a little in size in proportion as the vitellus di- 
minishes ; but it remains at length stationary,—relations which 
exist in all known animals. When we examine very developed 
ovaries, we find that the youngest ovules are appended to the 
stroma by a short pedicel, whilst the most advanced ovules, which 
are surrounded by a very visible chorion, are not provided with 
this pedicel. 
III. Tail :—Seminal cells —The cavity of the tail is divided 
throughout its length by a vertical partition attached to the 
transversal septum, which limits posteriorly the cavity of the 
trunk, and is thus divided into two cells perfectly independent of 
one another. It is in these cells, as we have already stated, that 
* There are however exceptions to this rule: the ovaries are sometimes 
less developed in the large individuals than in other smaller ones. I re- 
member in particular an individual the length of which was only three- 
quarters that of a norma] adult, and in which the fecundation nevertheless 
took place in the interior of the ovaries, which were highly developed. 
