of the most interesting of the Octopods. It is unique in 
the fact that the female alone possesses a shell, which is 
useful, not only as a nest for the eggs, but serves also as 
a nursery for the young. While the male Nautilus is only 
about an inch long, the female is much larger, and may 
occupy a shell upwards of nine inches in the largest dia- 
meter. There are no muscular attachments, as in other 
shellfish, and the animal retains possession of the shell by 
clasping the sides of the aperture with her two dorsal arms, 
thereby leaving six arms for swimming with and procuring 
food. The shell of the Argonauta Argo is sculptured with 
numerous ribs, which are somewhat close together, becom- 
ing nodular as they approach the keel. The keels are fairly 
approximate, and are furnished with sharp spines corre- 
sponding in number to the ribs. The aperture exhibits two 
ears or lugs, or everted angles, on the margin next to the 
spire, and the mouth extends outwards on either side at 
a right angle. 
Mayor Island, Bay of Plenty. 
ARGONAUTA TUBERCULATA (Argonaut, a com- 
panion of Jason in the ship “Argo” ; tubercle, a little knob). 
—This Nautilus differs very little from the A. Argo. The 
ribs are more numerous and the sharp spines on the keels 
are likewise increased and closer together. The ribs are 
cut up into little nodes or tubercles, and the mouth at its 
margin, next to the spire, curves gently down on either 
side. Fifty years ago an Argonaut shell in the Old Coun- 
try would fetch as much as £14, but at the present day 
there is little commercial value attached to them. 
Mayor Island, Bay of Plenty. 
TEREBRATELLA RUBICUNDA (terebratella, dim. 
terebratus, perforated; rubicunda, reddish).—These shells, 
popularly known as Rose Petals, from their pinkish-red 
shells, are of very ancient lineage, their ancestors being 
well represented in the Coal Measures. They are also 
called Lamp shells, in common with some other species of 
the same family, from their striking resemblance to the 
old Roman lamp, with the small round hole near the hinge 
corresponding to the hole for the wick of the little oil 
lamp. This aperture in the shell gives passage to a sinewy 
stalk, which is used by the animal to attach itself to stones, 
shells, etc., sometimes to shells of its own kind. Nothing 
in the shape of anchorage comes amiss to these queer 
Brachiopods, for I have seen in a friend’s collection an old 
jampot almost completely covered with the shells. The 
valves can be opened only to a slight extent without break- 
117 
Plate I 
No. 1 
Plate V 
No. 21 
Sea Shells 
of New Zealand 
