$ 140. 
THE ROTATORIA. 
149 
CHAPTER IX. 
ORGANS OF GENERATION. 
§ 140. 
Although it is certain that the Rotatoria propagate only by genital 
organs, yet the female organs only are yet well known. 
These consist of a 
single or double ovarian tube of variable length, situated upon the sides of 
the intestinal canal at the posterior part of the cavity of the body, and 
opening into the cloacal cavity through a short oviduct. 
never develop but a few eggs at a time. 
oval and surrounded by a simple, solid, colorless envelope. 
These ovaries 
The mature eggs are always 
They contain 
a finely granular and usually colorless vitellus, in which there is a distinct 
germinative vesicle. 
parous.” 
Many species are ovigerous, but a few only are vivi- 
It would be naturally supposed that these animals, which have such dis- 
tinct female organs, would have also those of the other sex. But as yet the 
most minute researches have failed to detect them. It is therefore doubt- 
ful whether these animals are hermaphrodites or of separate sexes.t 
1 For the various forms of the ovaries see the 
classical works of Ehrenberg. With Philodina 
roseola, Brachionus rubens, and Mastigocerca 
carinata, the vitellus of the eggs as well as the 
parenchyma of the body is of a reddish color. 
‘With those species which live in the tubes, the 
eggs are usually deposited in the cavity of these 
dast. But with Triarthra, Polyarthra, and 
Brachionus, they remain glued to the cloacal 
opening. 
With Philodina, the young are often hatched 
in the cavity of the parental: body, and are, accord- 
* [§ 140, note 1.) The view here expressed that 
the young of the viviparous Philodinae may find 
their escape from the body of the parent through 
gn opening near the anus—the oviducts being 
perhaps wanting — is probably correct, since, in the 
viviparous Aphides, where the processes of repro- 
duction occur likewise by a kind of gemmiparity, 
there are, according to my observations, no ovi- 
ducts proper, but the young, having fallen into the 
abdominal cavity, thence escape through a Porus 
genitalis situated near the anus. — Ep. 
t [End of § 140.] The discovery of distinct 
males with the Rotatoria is due to Brightwell 
(Ann. Nat. Hist. Sept. 1848) who has positively 
determined it with Asplanchna. Here it is about 
half. the size of the female, being also of a different 
form; it is exceedingly transparent and easily eludes 
observation, The testis appeared as a round yes 
sel situated at the bottom of the body on one side, 
and filled with spermatic particles. This author 
13* 
ing to Ehrenberg (Die Infusionsthierchen p. 483), 
always surr d with an ex ible membrane 
of the ovary (uterus), But it has always appeared 
to me that the mature eggs of the viviparous Phi- 
lodinae, are detached from the ovaries and fall into 
the cavity of the body, where afterwards the 
hatched young move about. Perhaps oviducts are 
here wanting and the young escape from their 
parent through an orifice near the cloacal open- 
ing.* : 
2 Admitting that there are here male genital 
organs, the respiratory tube upon the neck of 
thinks also that he observed a well-defined intro- 
mittent organ connected with the testis, and a 
passage for its extension from the body of the 
animal. 
In verification of this observation it may be men- 
tioned that Brightwell observed the actual coitus 
between the sexes, and Gosse (loc. cit. p. 22) has 
witnessed the development of the males from the 
ovum. 
Huczley, on the other hand (Quat. Jour. Mic. 
Se. No. I. Oct. 1852, p. 1), has found with Lacin- 
ularia no trace of a male individual, but in some 
specimens he observed singular bodies which 
answered precisely to Kélliker’s description of the 
spermatic particles of Megalotrocha. He says, 
“They had a pyriform head about 1-1000 in. in 
diameter by which they were attached to the parietes 
of the body, and an appendage four times as long 
which underwent the most extraordinary contor- 
tions, resembling however a vibrating membrane 
