long.

The _Colours_ (after having been long in spirit) of the valves have
already been given; sack and peduncle dirty yellowish-brown, with the
parts corresponding to the margins of the valves much darker brown, or
almost black; segments of the cirri clouded with dark brown; body and
pedicels of the cirri dirty yellowish. I have reason to believe that the
colours are totally different in living specimens.

_Monstrous Varieties._--Most of the specimens from lat. 50 deg. S., on
the coast of Patagonia, were more or less deformed, with the successive
zones of growth overlapping each other, and forming coarse concentric
ridges. The carina in several specimens was laterally distorted.

I have already remarked that this species has some affinity to _L.
pectinata_; but it is much more closely related to _L. fascicularis_,
the affinity being clearly shown by the thinness and translucency of the
valves, their convexity, by the width and little acumination of the
upper part of the carina, by the width of the fork, and by its not being
deeply imbedded. In young specimens, moreover, before the fork is fully
developed, there is a remarkable similarity between the two species, in
the form of this lower part of the carina. Again, the narrowness and
inflection of the peduncle under the capitulum in _L. australis_, and
lastly, the lateral marginal spines on both sides of the segments of the
posterior cirri, all clearly indicate this same affinity to _L.
fascicularis_.

I believe this species is confined to the southern ocean; and perhaps
there represents _L. fascicularis_ of the northern and tropical seas. It
must, judging from the number of specimens brought home by Captain Sir
J. Ross, and from those previously in the British Museum, and from those
collected by myself, be a very common species.

6. LEPAS FASCICULARIS. Pl. I, fig. 6.

LEPAS FASCICULARIS. _Ellis_ and _Solander_. Zoophytes, 1786, Tab.
xv, fig. 5.

---- ---- _Montagu._ Test. Brit. Suppl., 1808, pp. 5, 164.

---- CYGNEA. _Spengler._ Skrifter Naturhist. Selbskabet, Bd. i,
1790, Tab. vi, fig. 8.

---- DILATA. _Donovan._ British Shells, 1804.

PENTALASMIS FASCICULARIS. _Brown._ Illust. Conch., 1844, Pl. li,
fig. 2.

---- SPIRULICOLA (!) et DONOVANI (!) _Leach._ Tuckey's Congo
Expedit., p. 413, 1818.

ANATIFA VITREA. _Lamarck._ Animaux sans Vertebres.

DOSIMA FASCICULARIS. (!) _J. E. Gray._ Annals of Philosophy,