(_b._) Spinose projections above the rudimental valves; at
the bottom of the figure are represented, as seen through
the whole thickness of the animal, the prehensile larval
antennae.

(_d._) The depression for the attachment of the adductor
scutorum muscle of the hermaphrodite; see fig. 15 _a'_.

(_e_, _e._) A transparent layer of chitine, which forms a
border to the occludent margin of the scutum of the
hermaphrodite. This border supports long spines, which are
connected with the underlying corium by sinuous tubuli.

10. The basal (normally anterior) portion of the above
complemental Male, greatly magnified, viewed dorsally from
above, exhibiting the larval prehensile antennae, attached
to the antero-sternal surface of the animal.

11. One of the antennae of ditto, viewed laterally and on the
outside.

12. Ditto, ultimate segment of.

13. Body of the above complemental male, consisting of the thorax
supporting the four pairs of limbs, and of the terminal
abdominal lobe.

14. Small portion of the outer integument of the complemental
male, as seen with a 1/8th of an inch object glass.

15. _Scalpellum vulgare_ (hermaphrodite), magnified three times.

(_a, a._) Complemental males.

(_b._) Rostrum, of which a separate enlarged figure (_b'_)
is given.

15_a'._ Scutum of the hermaphrodite _Scalpellum vulgare_,
internal view of.

(_a._) Fold on the occludent margin.

(_d._) Pit for the adductor muscle.

TAB. VI.

Fig.

1. _Scalpellum ornatum_, (female, magnified seven times.)

1_a'._ _Scalpellum ornatum_, Upper latus, viewed internally.

1_b'._ _Scalpellum ornatum_, Scutum of full-grown specimen, viewed
internally, much magnified.

(_a._) Depression for the adductor muscle.

(_b._) Depression for the reception of the male.

1_c'._ _Scalpellum ornatum_, cutum of half-grown specimen, viewed
internally, much magnified, on same scale with fig. 1 _b'_.
The depression (_b_) for the reception of the male is here
seen, in almost the first stage of formation.

1_d'._ _Scalpellum ornatum._ An imaginary section through the
cavity (_x_) in which the male is lodged.

(_a._) Section of the shell of the scutum of the female.