a 
182 PYRAMIDULA ROTUNDATA. 
The SUPRA-PEDAL GLAND is comparatively well developed, and occupies nearly 
all the hinder part of the foot, but is quite deficient of the roof folds, so con- 
spicuous in many species. This is also one of the few 
species in which pigment cells are found mingled with 
the gland cells, while behind and above the oland there 
is a large and well-defined BLOOD-SINUS or lacuna. 
The REPRODUCTIVE ORGANS of Pyramidula rotundata 
display the simplicity characteristic of the Haplogona, 
being deficient of dart, flagellum, and mucus glands ; the 
whitish OVOTESTIS is composed of acini arranged in a long 
and narrow series, and is imbedded in the DIGESTIVE 
GLAND; the white HERMAPHRODITE DUCT is very long, 
much enlarged, and closely convoluted in the middle, ter- 
minating at the base of the conspicuous RECEPTACULUM- 
SEMINIS which is cleft at the apex and slightly pigmented ; 
the ALBUMEN GLAND is narrow, almost lanceolate, and 
of a brown colour tinged with green; the SPERM-DUCT 
or prostate is very broad, covered with elongate, loosely 
adherent, opaque, milk-white nodules, apparently charged 
with lime; OvVIDUCT yellowish-grey, modertucly. ample, 
and sacculate ; free oviduct narrow and direct ; the PENIS 
SHEATH, which is looped by the retractor of the right 
ommatophore, is very large, massive, and white, with the 
distal end abruptly ‘deflected or bent; the stout PENIAL 
RETRACTOR being attached to the convex side and to the 
oviduct ; VAS DEFERENS simple, and entering the penis 
sheath at its distal extremity ; SPERMATHECA whitish, 
elongate-oval, with a very long and slender blackish stem 
PAL 
Fic. 237.— Reproductive 
organs of P. votundata X 5. 
h.d. hermaphrodite duct ; 
o. ovotestis; a.g. albumen 
gland; ov. oviduct; v.d. 
vas deferens; 7. retractor 3 
p.s. penis sheath ; sf. sper- 
without a diverticulum ; ATRIUM short. matheca ; #7. prostate. 
The JAW or mandible is about half-a-millimetre in width from side to side, 
and only slightly arched, with a blunt and slightly- 
projecting median beak or rostrum ; narrow and 
with upper and lower margins almost parallel the 
whole length, and showing very indistinet and deli- 
cate intermediate striation ; pale amber in color, 
becoming colourless and almost transparent along 
the upper margin ; numerous delicate vertical folds 
indistinetly crenulate the cutting-edge, but do not 
reach the upper margin, while a ‘Jesser number but Barrett- Hamilton ; preparation by 
stronger and more decided in character, arise from Mr. J. W. Neville). 
the upper margin, and usually extend across the jaw to the cutting-edge ; 
are slightly rounded with the lower angles acute. 
The RADULA is of the usual oblong shape, and consists of about one hundred 
sinuately transverse rows, each row composed of a rather long aud narrow tricuspid 
mid-tooth, bearing a strong mesocone with a rather insignificant ectocone at each 
P 
é ai 
Fic. 238.— Mandible or jaw of 
Pyramidula rotundata, X 50. 
(Kilmanock, Wexford, Mr. G. 
the ends 
FOR gp 
Fic. 239,—Half a transverse row of teeth from the radula of P. votundata, highly magnified, 
Kilmanock, Wexford (Mr. G. Barrett-Hamiiton ; preparation by Mr. J. W. Neville). 
side ; the laterals are bicuspid, being deficient of the endocone, but possess a stiong 
and obliquely directed mesocone and a comparatively small ectocone ; the marginals, 
which are seven or sometimes eight in number, are tricuspid, displaying in addition 
to a large and powerful mesocone and a strong ectocone, a closely appressed and 
insignificant endocone, which becomes more distinet as the mar gin is approached. 
The dental formula of a Kilmanock specimen is $+$+}+$4+4x 100=3,100. 
