216 MOLLUSCA. 
by exposure to the atmosphere, like the epidermis of the Mytili, 
breaking at the same time the fragile shell. This would not be the 
case were the shell designed for exposure to the atmosphere. Ampul- 
lacera fragilis, as described by Quoy and Gaimard, appears to be allied 
to this shell; and I venture, for the present, to associate it with that 
genus. Asa further reason, we may add the fact that this, as well as 
the described species of Ampullacera, are peculiar to New Zealand. 
SIGARETUS ANTARCTICUS, (Couthouy, MS.) 
AnimaL remarkable for the delicacy and beauty of its coloration. 
On a deep orange-coloured ground, the back exhibits numerous, small, 
reticulating lines, so intersecting as to form little parallelograms ; 
these are bordered with white dots, and the intervals covered with 
larger ones of bright yellow. The under side of the mantle is very 
broad, and of a delicate rose-colour, margined by a narrow line of 
dark red, veined with radiating lines. The foot is lemon-coloured, 
paler along the middle. All the colours of the under side have a 
semitransparent look. Form of the animal broad-oval, very convex, 
highest at the anterior third; the mantle extends far beyond the 
foot, except posteriorly, where the foot projects some distance; it is 
deeply cleft in front, or rather forms a deep sinus or aquiferous canal 
to the branchiz, on the under side, which above appears like a deep 
sinus or emargination. The head is broad, and capable of great ex- 
tension, with a transverse cleft below, giving exit to an enormous 
proboscis, largest at its extremity, with a vertical fissure at tip. ‘Ten- 
tacles at each angle of the head, conical, compressed ; eyes on a lateral 
enlargement near the base, very prominent. Foot nearly square in 
front, with a very deep fissure across; the upper margin thus formed 
projects a little beyond the side of the foot, in a sort of laciniation ; 
posteriorly, it is narrowed considerably, and projects a little behind 
the mantle. 
SHELL not observed, but presumed to be quite flexible, as when 
contracted by alcohol the shape is altogether altered. 
Length an inch and three-fifths ; breadth an inch and one-fifth. 
Obtained by Midshipman Elliot among stones, at low tide, Orange 
Harbour. [J. p. c.] 
