- Fig. 1 a, Pachylasma aurantiacum, shell, lateral view;
A, rostrum, separated only by the finest suture from
B, the rostro-lateral compartment, which latter has a mere rim-like
radius on the side facing the lateral (C) compartment.
The latter (C) has a great ala, and is separated from the
(D) carino-lateral compartment, by the finest suture;
D has a rim-like radius;
E, carina, with very large alæ (a).
- 1 b, Pachylasma aurantiacum, inside view of about half the shell,
showing the compound rostrum, consisting of the true
rostrum (A) and the two rostro-lateral (B, B) compartments;
of the latter, that to the left has a shoulder, receiving the
ala of the lateral compartment which has been removed;
the ala of the lateral compartment extends, in the upper
part, over the whole width of the rostro-lateral compartment,
as may be seen on the right-hand, B; C, lateral
compartment;
D, carino-lateral compartment, with a
shoulder (b) to receive the ala of the carina, which has been removed.
- 1 c, 1 d, Pachylasma aurantiacum, scutum and tergum, external views of.
- 2 a, Octomeris angulosa, shell seen from above;
2 b, scutum and tergum, internal views of.
- 3 a, Octomeris brunnea, shell seen from above;
3 b, scutum and tergum, external views of.
- 4 a, Catophragmus polymerus, shell seen from above.
- 4 b,””external view of one of the scales or valves, from the second whorl,
counting from the inside.
- 4 c,””outline of the basal edges of all the
valves of a shell;
A, rostrum;
B, rostro-lateral;
C, lateral;
D, carino-lateral compartments;
E, carina.
- 4 d,””external view of a portion of the shell of a much corroded and worn
down specimen, serving almost as a transverse section;
C, lateral compartment,
D, carino-lateral compartment.
- 4 e,””scutum and tergum, internal views of.