to show the internal structure. The specimen is in the
College of Surgeons.

6_a._ _Lepas fascicularis_, carina of, nat. size.

6_b._ _Lepas fascicularis_, var. _villosa_.

6_c._ _Lepas fascicularis_, var. _villosa_, carina of.

6_d._ Part of the membrane from one side of the peduncle of _Lepas
fascicularis_, with the ball removed, showing one of the
cement-ducts, and the orifices through which the vesicular
membrane forming the ball has been secreted; greatly
magnified; viewed from the outside.

TAB. II.

Fig.

1. _Poecilisma Kaempferi_, (magnified two and a half times.)

1_a._ _Poecilisma Kaempferi_, carina of.

2. _Poecilisma aurantia_, (magnified two and a half times.)

3. _Poecilisma crassa_, (magnified twice.)

3_a._ _Poecilisma crassa_, carina of.

4. _Poecilasma fissa_, (magnified five times.)

5. _Poecilasma eburnea_, (magnified five times.)

5_a._ _Poecilasma eburnea_, carina of, external view of.

5_c._ _Poecilasma eburnea_, carina of, lateral view of.

5_b._ _Poecilasma eburnea_, scutum, internal view of.

6. _Dichelaspis Warwickii_, (magnified five times.)

6_a._ _Dichelaspis Warwickii_, transverse section of the top of
the peduncle, showing the deeply-notched end of the inwardly
bent carina; magnified five times.

6_b._ _Dichelaspis Warwickii_, _var._, scutum and tergum.

7. _Dichelaspis pellucida_, (magnified five times.)

7_a._ _Dichelaspis pellucida_, basal end of carina of, much
magnified.

8. _Dichelaspis Lowei_, (magnified nearly ten times.)

8_a._ _Dichelaspis Lowei_, fork of carina of, viewed internally.

9. _Dichelaspis Grayii_, (magnified eight or nine times.)

10. _Dichelaspis orthogonia_, (magnified six times.)

10_a._ _Dichelaspis orthogonia_, carina, lateral view of.

10_b._ _Dichelaspis orthogonia_, basal end of carina, viewed
internally, much magnified.

TAB. III.

Fig.

1. _Oxynaspis celata_, (magnified three times.)

1_a'._ _Oxynaspis celata_, with the skin of the encrusting horny
zoophyte removed. (_a_), scutum; (_b_), tergum; and (_c_),
carina.

2. _Conchoderma virgata_ (magnified twice.)

2_a._ _Conchoderma virgata_ carina, viewed externally.

2_b._ _Conchoderma virgata_ summit of capitulum, showing the terga
from vertically above.

2_c._ _Conchoderma virgata_ var. _chelonophila_,