MONCECIA— GYNOGAMA AND STYLOGAMA. 
357 
Fig. 
of 
651. — Reproductive organs 
Arion horiensis F^r., X 2, illustrating 
the Cryptophalliate Gynogama. 
<?/.ovotestis ; h.d. hermaphrodite duct ; 
pr. prostate ; v.d. vas deferens ; ep. 
epiphallus ; a.g. albumen gland ; ov, 
sacculated or glandular oviduct ; sp, 
spermatheca ; z>ag. vagina ; at, atrium ; 
v.g. vestibular gland ; r.;;?. retractor 
muscles attached to spermatheca and 
vagina. 
The Gynogama (yw-i], female ; ya/j-os, marriage) are confined in 
this country to the Ar'ionidw, and are particularly charactei’ized by 
the atrophy and loss of the male 
intromittent organ, and the transfer 
of its function and retractor muscles 
to the vagina and spermatheca which 
usurp its function and are everted 
during copulation, the male portion 
being merely the amplified sperm 
duct or epiphallus which moulds the 
spermatozoa in the form of a sperma- 
tophore for transference to the 
copulatory pouch of its mate. The 
atrium or vestibule which opens be- 
neath the pulmonary orifice on the 
right side of the body is enveloped by 
a dense glandular pad which may 
represent the digitate glands of the 
Stylogama. 
The Stylogama (srfAos, a rod; ydfj-o^, marriage) are the most 
complexly organized of the ]\Iono- 
tremata, often developing a number 
of highly differentiated organs in 
connection with the reproductive 
function. 
The female organs possess highly 
specialized vaginal prostates or 
vesiculm multifidse in the form of 
ramified digitate glands, which are 
usually paired and placed at each 
side of the vagina, into which they 
open ; the number of these glan- 
dular digitations varies greatly in 
the diflferent species, or even in the 
same species ; there may be few or, 
as in Helix pomatia, they may, 
though vaiying greatly individually 
reach thirty or forty digitations to 
each gland. 
Fig. 652. — Reproductive organs of Helix 
lapicida L., X 2, illustrating the Crypto- 
phalliate Stylogama. 
ot. ovotestis ; h.d. hermaphrodite duct ; 
p7\ prostate ; v.d. vas deferens ; Jl. flagellum; 
ep. epiphallus; p.s. penis sheath; r. penial 
retractor ; cn>. sacculate oviduct ; sp. sperma- 
theca ; d. its diverticulum ; vi.g. digitate 
mucus glands ; d.s. dart sac ; vag. vagina. 
