Gastekopoda. ilOLLUSCA. Pkobosciuifeka. 
332 
Genus Triton. — The True Trumpet shells have the 
varices disconnected, and so arranged as to form three 
interrupted longitudinal ribs. The canal is prominent, 
and the lips denticulate. The species are principally 
equatorial in their geographical distribution, belonging 
more especially to Asia. Those which have a much 
produced canal are obtained from deep water; tliose 
which have a cancellated surface are from sand in 
deep water ; and those covered with an epidermis are 
chiefly from sandy mud, in from six to thirty fathoms. 
TRITON VARIEGATUS is the shell well known by 
the name of “the JIarine Trumpet or Triton’s Shell,” 
and is one of the finest, as it is certainly the largest 
Fig. 218. 
Triton variegatns. 
species (fig. 218). It is elongate, conical, trumpet- 
shaped, ventricose in the last whirl, and girt with very 
obtuse smooth ribs of a white colour, elegantly varie- 
gated with red and bay. The aperture is red, and the 
columellar lip is wrinkled with white. This large shelj 
is a native of the West Indian and the Pacific oceans, 
and is the conch used by the Australian and Polynesian 
islanders as a war trumpet. Captain Cook remarks, 
that during his visits to the Australasian islands, he 
never knew the blowing of the conch amongst the 
natives to portend good ; it always seemed to be the 
signal for a hostile attack. i\Ir. Ellis, in his “ Polynesian 
Researches,” however, informs us that these conches 
were blown in processions to their temples, at the inau- 
guration of a king, duiing their worship at their temples, 
or when a tabu or restriction was imposed in the name 
of the gods, as well as when their warriors marched to 
battle. “ We have sometimes heard them blown,” be 
says. “ The sound is extremely loud, but the most 
monotonous and dismal that it is possible to imagine.” 
This trumpet is also used in the West Indian islands 
to summon the negro labourers to their work. A 
species somewhat similar is found in the Mediterra- 
nean (Triton nodiferus), and it is no doubt of this 
shell that Dr. Johnston speaks when he says, it is 
“ clearly the original of the war trumpet.” 
Genus Ranella. — THE FROG-SHELLS oi-Ranella; 
{Apollon) have their varices arranged two on each whirl, 
and so disposed as to form a border to the shell on 
each side. The shell is compressed, and has a short, 
straight canal. The species are mostly tropical, the 
majority being from the Eastern seas. Upwards of fifty 
species have been described, ranging from low water to 
twenty fathoms. The variegated species, which have 
the whirls nodosely armed, are found in rocky [>laces 
and on coral reefs ; the winged species, with a smooth 
surface, are from deep water. They move about with 
considerable animation, and crawl rapidly. As observed 
by Mr. A. Adams, in the Philippine islands the Ranellse 
seemed to move about much more briskly than might 
have been anticipated from animals furnished with such 
a heavy .shell ; thrusting out their head, protruding 
their tentacles and proboscis, and ascending even per- 
pendicular substances wiih considerable facility. “One 
species,” says Mr. Adams, “dredged from twenty 
fathoms water, was furnished with a very extensive 
proboscis, which it was able to exsert to the distance 
of two inches from the head, using it as a perceptive 
oigan, in the same manner as the elephant does its 
trunk.” 
Passing by the families Sycotypidse and Velutinida’, 
we come to the — 
Family— NATICID.®. 
The family of NATICAS (Naticidee) are remarkable 
among the proboscidiferous mollusks for their very 
large foot. It is much produced in front, and is 
there provided with a well-developed fold, which 
becomes a great lobe, reflexed upon and concealing 
the head, with the exception of the tentacles, which 
are rather small, and united by a transverse membrane. 
The operculigerous lobe is very largely developed, 
reflected upon and partially covering the sides and 
back of the shell, which indeed has the appearance of 
being as it were sunk into its substance. The oper- 
culum is sjiiral, horny, or covered with a shelly external 
coat, and though of good size is not very apparent on 
the animal, being placed transversely and hidden by 
the extremity of the shell. The mantle is inclosed 
and has no siphon, the mouth of the shell being also 
entire in front and destitute of a canal. The species 
present marked characters — the shells being in general 
spiral, more or less globular, and usually smooth and 
polished on their surface. The epidermis is generally 
