128 THE GASTROPODA 
Nudibranchs, the stylet being contained in a special pouch in 
certain species of Doris: in some other Nudibranchs there are 
multiple stylets. 
In addition to the bursa copulatrix, there are numerous and 
various accessory genital organs in the hermaphrodite Gastropoda. 
An albuminiparous and a mucous gland are found on monaulic ducts, 
generally near their distal end (Fig. 171, 
muc). In the diaulic Pulmonata there 
is a large albuminiparous gland on the 
hermaphrodite section of the duct (Fig. 
104, #.d), and on the female part of the 
duct of Basgmmatophora there is an 
albumen gland corresponding to the 
uterine glands of Stylommatophora (Fig. 
104, wv). The diaulic and triaulie Opis- 
thobranchs have also contiguous albumen 
and mucous glands on the oviducal part 
of the genital duct. The terminal portion 
of the oviduct of Stylommatophora is 
further provided with a glandular zone 
(Zonites), or with two multifid vesicles 
with a variable number of ramifications 
Limapontia, reproductive appara. (Eig. 104, d). Opening between the 
tus, dorsal aspect. a.d, albumini- two 1S a special pouch —seemingly a 
parous duct; a.g, albuminiparous O40 5 : . 
sland; h.d, hermaphroditic duct; Specialised multifid vesicle, which secretes 
Fe Oe as, mo; mucous Ovi 4 sharp calcareous dart (Fic..l04, gis) 
dueal gland; 0.0, oviducal orifice ; : : é 
ov, oviduct; p, penis; pr, pros- Before copulation the dart-sac is evagin- 
SaaS ee ores ened together with all the terminal 
part (vestibule) common to the repro- 
ductive organs, and the dart, which is caducous, pierces the 
skin of the conjugate. The spermiduct is sometimes furnished 
with amore or less elongate “prostate” gland, as in Valvata, 
Oneidiopsis (Fig. 103, pr), various Bullomorpha and Elysiomorpha 
(Fig. 105, pr). The penis of certain Stylommatophora is provided 
with a long hollow caecum, the “flagellum” (Fig. 104, #/), in the 
interior of which is secreted the spermatophore or capreolus. 
This is a thin-walled chitinous tube closed at one end and cleft 
at the other and filled with a quantity of sperm. When there is 
no flagellum the spermatophore is formed by the deeper portion 
of the penis. Sometimes the spermatophores are furnished with 
denticulations and even with arborisations (Fig. 106). 
The hermaphrodite gland (gonad) does not liberate ova and 
spermatozoa simultaneously, the discharge of the former occupying a 
very short time after copulation. Generally speaking, the hermaph- 
roditism is protandric, the spermatozoa being the first of the 
genital products to come to maturity. This hermaphroditism is 
