2 MOLLUSCA, 
a point; aperture consisting of a small produced siphon; colour, when divested of its 
brown epidermis, pure white and glossy. Length one-tenth of an inch. Inhabits 
the sea at Sandwich. 
2. N. decemlocularia. 
Shell with ten distinct, nearly globular articulations; slightly arcuated, and ending 
in a long tapering articulation, in which the septaare hardly distinguishable; covered 
with a reddish-brown epidermis. Length a tenth anda half of an inch. We have 
received this from the south coast of Devon; but too late for insertion in the plate. 
This is doubtless the same she!l which Montagu considers a variety of N. subar- 
cuata, which he had from Sandwich. 
3. N. radicula, pl. 1, f. 28.—Orthocera radicula,—First Ed., pl. 52, f. 28; Nau- 
tilus radicula ; Montagu, p. 197, pl. 6, f. 4. 
Shell subconic, elongated, with six subglobose deeply divided articulations; the 
upper one much larger than the others, and egg-shaped, smooth, opaque-brown, 
and the aperture provided with a small siphon, with the apex extended to a conic 
point. From Sandwich. 
Montagu mentions varieties of this species, having from two to five articulations. 
We have not seen these, and therefore cannot speak concerning them. The follow- 
ing distinct species is only considered a variety by that able naturalist. . 
4. N. octolocularia, pl). 1, f. 25.—Orthoceru radicula.—First Ed., pl. 52, f. 25; 
Nautilus radicula ; variety. Montagu, 198, pl. 14, f. 6. 
Shell with eight round sub-compressed articulations, the superior one nearly 
spherical, with a small circular aperture in the apex; the remaining articulations 
gradually lessening, and the last one somewhat pyriform and pointed at its extremity. 
Colour cream-white. Found at Sandwich and the south coast of Devon. 
In our first edition we followed Montagu, in considering this only a variety of 
N. radicula. 
5. N. spinulosa, pl. I, f. 26.—Orthocera spinulosa.—First Ed., pl. 52, f. 26; 
Nautilus spinulosus ; Montagu, Sup. p. 86, pl. 19, f. 5. 
Shell with three globose, deeply divided articulations, covered with spines, which 
incline to the posterior end; the superior bulb somewhat elongated, in the form of a 
siphon ; colour pale chestnut. 
Montagu mentions a variety of this shell, of which he possessed a drawing by Mr 
Henry Boys, which was subarcuated and taper, with eight articulations ; which were 
rather tuberculated than spined. We would be inclined to consider this a distinct 
species, under the trivial name of tuberculata. 
Genus 4.—OrtTHocEeRA.— Lamarck. 
Shell elongated, straight, or a little arcuated, subconical; gene- 
rally ribbed, with longitudinal, external grooves ; chambers formed 
by transverse septa, perforated by a tube, which is either central or 
marginal. 
Subdivision I.— Ribbed. 
1. O. costata, pl. I, f. 17.—First Ed., pl. 52, f. 17; Nautilus costatus; Mon- 
tagu, p. 199, pl. 14, f. 5. 
Shell straight, subcylindrical, tapering slightly towards the posterior termination ; 
with twelve convex articulations, each provided with four equidistant, stronz longi- 
tudinal ribs, running continuously the whole length of the shell; aperture extended, 
in the form of a short conic siphon. Length a quarter of aninch. Found on the 
coast of Kent. 
Montagu mentions a variety, with only six articulations, for the same locality. 
2. O. septemcostata, pl. I, f. 24.—O. costata, variety, First Ed., pl. 52, f. 24; 
Nautilus costatus ; Montagu, Sup. variety, p. 83, pl. 19, f. 2. 
Shell nearly cylindrical, with five oblong-ovate articulations, each provided with 
seven ribs, running continuously the whole length of the shell; posterior end trun- 
cated, with the points of the ribs projecting beyond its margin; anterior end termi- 
nated by a slender cylindrical process as long as the first articulation, destitute of any 
opening, the aperture being situated at the truncated extremity. 
Montagu mentions a variety with five articulations, and four ribs only. 
3. O. jugosa, pl. I, f. 15.—First Ed., pl. 52, f. 13; Montagu, p. 198, pl. 14, 
f. 4. 
Shell subarcuated, subcylindrical, tapering; with nine, ridged, subglobose, some- 
what elongated articulations ; aperture extended to asmall conic siphon, the extreme 
joint at the inferior end rather longer than the contiguous ones; colour opaque- 
brown. Length a little more than an eighth of aninch. The ridges do not extend 
quite to the top of the articulations. 
4. O. bicarinata.— Nautilus bicarinatus.—Montagu, Sup. p. 86. 
Shell areuated, subcylindrical, with eleven subglobose, bicarinated articulations, 
or furnished with a slight longitudinal rib along the are, and another on the opposite 
side; the larger end terminated by a produced siphon; the articulations gradually 
ecrease towards the posterior end, which is rounded; length an eighth of an inch ; 
diameter at the largest part about tne same. Found at Sandwich. 
5. O. linearis, pl. I, f. 14—15.—First Ed., pl. 52, f. 14-15; Nausilus linearis ; 
Montagu, Sup. p. 87, pl. 30, f. 9. 
Shell straight, a little compressed, linear, slightly tapering ; provided with numer- 
ous longitudinal ribs, which take an oblique direction, and scarecly extend half the 
[CerHatorona. 
length of the shell. It is of a glossy, smooth, and pellucid white, except along the 
sides, and at the divisions of the cells, where it is opaque ; ther» are about fourteen 
slightly oblique, and not quite regular septa; anterior extremity smooth. and ter- 
minated by a produced siphon; posterior end rounded. Length nearly a quarter of 
an inch, breadth about an eighth of its length. Found onthe shell-bank at Dunbar, 
Frith of Forth. 
Subdivision Il.—Destitute of Ribs. 
6. O. recta, pl. I, f. 16, 19, 20.—First Ed., pl. 52, f. 16, 19, 20; Montagu, 
p- 197, and Sup. p. 82, pl. 19, f. 4 and 7. 
Shell straight or very slightly arcuated, with perfectly smooth, slightly divided 
articulations ; tapering a little to the posterior termination; aperture situated in a 
small produced siphon at the anterior extremity. Found at Sandwich; very rare. 
Famity 1V.—SpPuHERULACEA. 
Shell globular, spheroidal, or oval ; with the volutions mutually 
enveloping, or the cells contiguous, and forming a tunic. 
Genus 5.—Bitocutina.—D’ Orbigny. 
Shell ovate-globose, with two transverse cells, involving the axis. 
1. B. oblonga, pl. LVI, f. 38-39.—Lagena oblonga.—First Ed., pl. I, f. 88,39; 
Vermiculum oblongum; Montagu, p. 522, pl. 14, f. 9. 
Shell oblong, oval, somewhat compressed; with a longitudinal suture on one side, 
which divides the shell into two parts; on the opposite side the middle compartment 
is surrounded by a faint depression, which separates it from the exterior one, and is 
more elevated , aperture oval, slightly produced, with a yellow margin; general eo- 
lour opaque, glossy white. Length not half a line. Found in sand from Saleomb 
Bay, Devonshire; rare. 
2. B. elliptica, pl. LVI, f. 23.—Milicla elliptica.—First Ed., pl. 1, f. 23. 
Shell elliptical, a little compressed, clear, smooth and glossy ; the internal cham- 
bers shining through, giving it the appearance of being externally grooved; size not 
aline. Found at Dunbar by General Bingham. 
3. B. lactea, pl. LVI, f. 28.—Miliola lactea.—First Ed. ; Vermiculum lacteum ; 
Montagu, p. 522; Serpula tenuis ; Walker, f. 5. 
Shell thin, smvoth, glossy, egs-shaped, slightly compressed; pellucid, with milk- 
white veins. Length half a line. Coast of Devonshire. 
4. B. marginata, pl. LV1, f. 25 —-Renoidea marginata.—First Ed., pl. a, 7. 255 
Vermiculum marginutum ; Montagu, p. 524; Walker, pl. 1, f, 7. 
Shell globular, a little compressed, surrounded by an elevated zone; colour 
white, transparent and glossy. Size not half a line. Found at Reculver, and on 
the coast of Devon; very rare. 
Genus 6.—TritocuLina.—D Orbigny. 
Shell generally ovate-globose, with three transverse cells inyoly- 
ing the axis. 
1. T. glabra, pl. LVI, f. 20-21.—Renoidea glabra.—First Ed., pl. 1, f. 20-21. 
Shell nearly circular, three lobed, the two external ones longest, and involving 
the third; smooth, transparent and glossy. Size about a line. Found at Dunbar 
by General Bingham; rare. 
2. T. rotundata, pl. LVI, f. 14-15.—Renoidea rotundata.—First Ed., pl. 1, f. 
14-15. 
Shell perfectly globular, smooth, shining and transparent; milky white, with 
three lobes, the external ones largest. Size not a line. Found at Dunbar by 
General Bingham ; very rare. 
3. T. bicornis, pl. LVI, f. 24.—Miliola bicornis.—First Ed., pl. 1, f. 24. 
Serpula bicornis ; Montagu, p. 519. 
Shell three chambered, the middle one sma’l, the outer ones rounded, considera- 
bly larger, and investing it on one side, and longitudinally striated on the longer 
side from the aperture, which is contracted ; mouth small, orb:cular ; colour opaque ; 
white. Length one line. Found at Sandwich and Reculver. 
4. T. perforata, pi. LVI, f. 26.—Milivla perforata.—F.rst Ed., pl. 1, f. 26 
—Vermiculum perforatum ; Montagu, p. 519.—Serpula bicornis ; Walker, f. 3. 
Shell three chambered ; central compartment flat, thin, and perforated, with a se- 
milunar dise on one side, and a larger curved chamber on the other; colour white, 
opaque, and glossy. Found at Sandwich and Cornwall; very rare. 
5. T. striata, pl. LVI, f. 27.—Miliola striata.—First Ed., pl. 1, facin 
Shell with three compartments, the two outer ones investi g the others; the 
whole are longitudinally striated ; yellowish white; nota line in length. Found at 
Belton sands, near Dunbar, by General Bingham. 
6. T. minuta, pl. LVI, f. 18-19.—Miliola minuta.—First Ed., p\. 1, f. 18-19. 
Shell three chambered, the middle one flat on one side, and raised on the other 5 
it is entirely invested by the outer valves, one of which is slender, and the other 
broad, and tapering, with three or four strongly marked longitudinal striz ; size 
about half a lime. Found at Dunbar by General Bingham. 



