PYRAMIDULA RUPESTRIS. P(t 
Original Description. —‘‘ Helix rupestris. Coquille brune, torse ; spire élevée, 
ouverture ronde, ombilie évasé. Haut. 2 mill., larg. 24 mill., diam. 24 mill. Habite 
France méridionale sur les rochers élevés (4 tours). Animal noiratre, plus pale en 
dessous. ‘Tentacules supérieurs courts, gros et trés-obtus; inférieurs a peine 
visibles & la loupe et semblables a de petits tubereules. Il redresse sa coquille, et 
la porte tres-élevée, lorsqwil marche.” —DRAPARNAUD, Tab]. Moll., 1801, p. 71. 
Description.—ANIMAL slate or dark-grey in colour with sometimes a reddish 
tinge, and covered with minute flattened TUBERCLES; the sides covered with 
numerous minute black specks, which are arranged in squares and form rather 
large spots; MANTLE dusky-brown, indistinctly speckled with black; Foor rounded 
in front, bluntly-pointed behind ; OMMATOPHORES divergent, dark grey in colour, 
thick and eylindrical, with large oval bulbular extremities ; the lower pair are 
almost rudimentary and nearly black. 
SHELL subconical, more depressed beneath, rather solid, glossy and dark-brown 
in colour, marked with close-set transverse strive, which encircle the whorls; 
PERIPHERY rounded, but angulated in young shells; WHORLS 4-5, cylindrical ; 
SPIRE somewhat raised; APEX rather glossy and transparent; SUTURE deeply 
impressed ; APERTURE deeply lunate, but compressed and without an internal rib ; 
OUTER LIP inflected, thin, simple, and slightly reflected in fully-adult specimens ; 
UMBILICUS large, open, and deep, exposing all the internal spire. 
Diam. 3 mill. ; alt. 2 mill. 
INTERNALLY, the REPRODUCTIVE ORGANS are described by Moquin-Tandon as 
showing a blackish HERMAPHRODITE DUCT; the PENIS-SHEATH as rather thick 
and not elongate, with a distinet and blunt swelling, which represents the flagellum 
at the distal-end, where the VAS DEFERENS also enters, slightly dilating before its 
entry therein ; SPERMATHECA oblong, borne upon a long stem, but destitute of a 
copulatory branch ; the DART-SAC and MUCUS GLANDS are also absent. 
The BUCCAL BULB is about a millimetre in length. 
The JAW is, according to Moquin-Tandon, about a 
third of a millimetre in width from side to side, slightly 
arcuate from back to front, and well and strongly arched, 
but difficult to distinguish amongst the tissues owing 
to its colour and transparency, although slightly tinged 
with amber along the thickened upper margin, the _ §36.226.—Jawof P. rupestris 
anterior surface presents fourteen to twenty somewhat RE aie a tN = 
indistinct flattened ribs, perceptible as faint delicate — eats 
vertical striation, which slightly crenulate the lower or cutting margin. 
The LINGUAL RIBBON is of the usual elongate shape, and composed of about 150 
obliquely sinnate transverse rows of teeth, each row formed by a trifid central tooth 
with a long and powerful mesocone ; there are about eight distinctly bicuspidate 
laterals, each with a thick mesoconic reflection and a more insignificant ectocone, 
which tends to be laterally bifureate ; the marginals are similar in character, about 
ten in number, and are only indicated by the change in the direction of the trans- 
verse row to which they belong, as the modification in the character of the teeth is 
almost imperceptible until the almost shapeless extreme marginals are reached. 
The formula of a Grange specimen, prepared by Prof. H. M. Gwatkin, is 
Coes 1 8 10 Xf) — © EEO 
DS +4454 42 x 150 = 5,550. 
Fic. 227.—Half a transverse row of the teeth of Pyramidula rupestris, highly magnified, 
Grange (from a preparation by Prof. H. M. Gwatkin). 
Reproduction and Development.— No observations have been 
made and nothing is known concerning the details of the conjugation of 
P. rupestris, but it is well recognized as one of our few ovo-viviparous 
species. 
This ovo-viviparity is well established, and examples have been fre- 
quently found in their usual haunts by many observers from August to 
October, containing from three to seven embryvos each; these embryonal 
