332 



Gasteropoda. - 



-SIOLLUSCA.- 



-Pkoboscidifera. 



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 tlie lips denticulate. The species are principally 

 equatorial in tlieir geographical distribution, belonging 

 more especially to Asia. Those which have a much 

 produced canal are obtained from deep water; those 

 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 VAEIEGATUS is the shell well known by 

 the name of " the Marine Trumpet or Triton's Shell," 

 and is one of the finest, as it is certainly the largest 



Fig. 218. 



Triton variegatus. 



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 shell 

 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 hobtile attack. Mr. 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, during 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," he 

 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 Eanella.— THE FROG-SHELLS orRANELLiE 

 {Apollon)\\3.ye 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 places 

 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 Philijipine islands the Eanellse 

 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 with considerable facility. " One 

 species," says Mr. Adams, " dredged from twenty 

 fathoms water, was furnished with a verj' extensive 

 proboscis, which it was able to exsert to the distance 

 of two inches from the head, using it as a perceptive 

 organ, in the same manner as the elephant does its 

 trunk." 



Passing by the families SycotypidiB and Velutinidse, 

 we come to the — 



Family— NATICID^. 



The family of NATICAS (Naticidm) are remarkable 

 among the proboscidiferous moUusks 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 spiral, 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 moutli 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 



