258 THE CEPHALOPHORA. § 227. 
It is only lately, that, from microscopical analyses of the contents of 
these parts, this point has been made clear. A peculiarity which distin- 
guishes principally the Pteropoda, Apneusta, Nudibranchia, Inferobran- 
chia, Tectibranchia, and Pulmonata, is the existence of a hermaphrodite 
gland. An exact knowledge of the structural relations of this gland has 
been the means of reconciling the hitherto confused opinions upon the geni- 
tal organs of the Gephalophora. 
This gland, which is nearly always buried in the substance of the liver, 
is composed of digitiform or botryoidal ramose caeca, bound together in 
groups of variable size forming a lobulated organ. Upon each caecum is 
an external sac, producing eggs, and an internal one, folded in the first, 
producing sperm. The walls of these two invaginated follicles are usually 
in direct contact, and are not separated from each other except at the 
points where there are eggs which push the ovarian sac outwards and the 
testicular one inwards. 
From these sacs pass off excretory canals, which, also, are invaginated, 
and terminate in two principal ducts, the external of which is the 
Tuba Fallopii, and the internal the Vas deferens which is usually tortuous. 
attributes to this last the function of an ovary 
(Beitr. zur Anat. d. Helicinen, loc. cit.), has ex-° 
pressed no positive opinion as to the function of 
the albumen gland. Steenstrup (Undersigelser 
over Hermaphroditismens Tilvaerelse i Naturen, 
1845, p. 76, Tab. II.) has expressed a very singu- 
lar opinion on the subject of the genital organs of 
the Pulmonata. He regards the Gasteropoda as 
of separate sexes with which the different parts of 
the genital apparatus are double, and that only one 
side is developed, the other remaining atrophied as 
in female birds. According to this, the hermaphro- 
aite gland would represent the active ovary, in the 
individuals which Steenstrup regards as females, 
and the albumen-gland would be the ovary on the 
other side imperfectly developed. The uterine canal 
would belong to the active side, the Vas deferens 
would be the abortive uterus on the other side, and 
the penis as an abortive analogous vesicle would 
correspund to the pedunculated vesicle of the active 
side. 
In the other individuals of the same species re- 
garded by Steenstrup as males, the hermaphro- 
dite glund would be the active testicle, and the al- 
bumeu-gland, the same organ on the other side, 
abortive ; the uterus would be the developed Vas 
deferens, and the proper Vas deferens the unde- 
veloped organ onthe other side. The pedunculated 
vesicle would have the same signification as with 
the female individuals, and the penis would be this 
vesicle imperfectly developed.* 
2 After R. Wagner (Wiegmann’s Arch. 1836, I. 
p. 370) had found in various Pulmonata, eggs and 
Spermatic particles at the same time in one and the 
same genital gland, and I myself had expressed my 
conviction (Ibid. 1837, I. p. 51) that with these 
4Gasteropoda the ovary and testicle were united 
in asingle organ, H. Meckel was the first who de- 
* [§ 227, note 1.] This structure —a hermaph- 
rodite gland — is not mentioned by Alder and Han- 
cock in their anatomical details of the Nudi- 
branchia; see loc. cit. With those genera (Acolis, 
Doris, &c.) with which they have given in special 
detail the generative organs, this combination of 
the two sexual organs is not spoken of. 
See especially Hancock and Embleton’s Anat- 
owy of Aeolis, Ann. Nat. Hist. 7 1848, p. 93, 
scribed exactly the structure of this hermaphrodite 
gland (Mudler’s Arch. 1844, p. 483, Taf. XIV. XV). 
It is, therefore, astonishing that Steenstrup 
(Underségelser, &c., p. 76, Tab. IL. fig. 3, 4), who 
knew the researches of Meckel, and who, judging 
from his figures, saw distinctly the line of separa- 
tion between the ovarian and testicular follicles, 
has determined two fragments of this gland taken 
from different individuals of Helix pomatia, 
as being one an ovary, and the other a testicle. In 
this last-mentioned fragment, he has called sperm- 
atic cells not only those really such.of the internal 
follicle, but also the eggs contained in the external 
follicle ; while in the first-mentioned fragment, or 
the so-called ovary, he has named as eggs not only 
the real eggs but also the internal spermatic cells. 
The spermatic particles, which he also saw at the 
same time, would, according to him, be brought out 
by coition. 
8 Under the Pteropoda, Kelliker (Denkschrift. 
&c. VIII. p. 39) has found the hermaphrodite 
gland with Hyalea. From this, the organs de- 
scribed by Cuvier, Eschricht, and Van Beneden, 
(Joc. cit.), as ovaries and oviducts with Clio, Cym- 
bulia, Cleodora, Cuvieria, Limacina, &c., may 
be regarded as an hermaphrodite gland, and as 
invaginated excretory canals. Under the Apneus- 
ta, this gland has been seen by Kéldiker, with 
Aeolis, Lissosoma, and Flabellina. It exists 
also with Actaeon, judging from the description 
of Alimann (loc. cit. p. 152, Pl. VI. VII. fig. 8) 
of its voluminous and multiramose ovaries, in 
which, he says there are observed, beside the pro- 
jecting sacs filled with eggs, others smaller filled 
with a granular substance. ‘The first are very 
probably ovarian, and the others testicular follicles. 
Tergipes, also, has a similar ramified ovary ; but 
it was incorrectly interpreted by Nordmann (loc. 
where the androgynous apparatus is minutely de- 
scribed, 
These authors affirm that although self-impreg- 
nation is, perhaps, possible, yet there is usually a 
congress of two individuals, and therefore a recip- 
rocal copulation. 
See also upon this point,—the real relations of the 
hermaphrodite gland, Gratiolet, Jour. de Conchol. 
1850, No. Il. p. 116. — Ep. 
