- Fig. 1 a, Platylepas bissexlobata, shell of, viewed from the under side;
A, rostrum;
B, lateral compartment;
C, carino-lateral compartment;
E, carina.
These letters are placed opposite the inward folds of each compartment forming the midribs.
- 1 b, Platylepas bissexlobata, shell of, viewed externally.
- 1 c,””scutum and tergum, viewed externally and separated.
- 1 d,””lateral compartment, viewed from the inside, showing the inward folded wall or midrib;
a′, ala; d, radius.
- 2 a, Platylepas decorata, shell, viewed externally;
A, rostrum;
B, lateral compartment;
C, carino-lateral compartment;
E, carina.
These letters are placed opposite the inward folds of each compartment.
- 2 b,””minute portion of external surface of wall, magnified.
- 3 a, Tubicinella trachealis, natural size;
p, tubular soft lip leading into sack; s, scutum; t, tergum.
- 3 b, Tubicinella trachealis, carino-lateral compartment of a young specimen, natural size;
e, broken summit of wall;
d, radius: the dotted lines, connecting the two figures, show the size
and form which this compartment would have attained, if it
could have grown without the summit constantly breaking away.
- 3 c, Tubicinella trachealis, scutum and tergum viewed from within, and connected by layers of thickened membrane;
the scutum is to the left-hand.
- 4 a, Xenobalanus globicipitis, enlarged;
b, skin of the porpoise, with the shell imbedded;
at c the lower end of the prosoma of the included animal’s body is supposed to be seen through.
- 4 b, Xenobalanus globicipitis, shell greatly enlarged, seen from above, with the basal membrane at the bottom; the
peduncle-formed body having been removed.
- A, rostrum, on the inner side of this and the adjoining compartments,
the transversely ribbed sheath can be seen.
- B, lateral compartment.
- C, carino-lateral compartment.
- E, carina; these compartments are separated by the sutures s s,
which run from the top of the shell to the bottom, along the
ends of the six rays formed by the adjoining portions of
the inwardly folded compartments.
- a, alæ, of rectangular shape.
- d, pseudo, or complimentary radii.
- 4 c, Xenobalanus globicipitis, small portion of external surface
of wall of shell, showing the external lamina, a a, which
consists only of narrow ledges (expanding and contracting)
on each side of the longitudinal septa, c; b, the internal
lamina.