GASTROPODS. 
375 
The gorgeously-coloured mitre-shells ( Mitridce) always have been and still remain 
a favourite group with collectors. Like the Marginellas, they have no operculum, 
and are small in comparison with the volutes, but they equal if not surpass them 
in the beauty of their colour-markings and surface sculpture. The columellar lip 
is always plaited, the hinder plaits being the strongest. A remarkable feature of 
the genus, at all events in some instances, is the enormous length of the proboscis, 
which seems to be out of all proportion to the animal. The tongue of the mitras 
has three rows of teeth, all serrated in some species, but in others, with the two 
laterals simple, and of a somewhat different type. The common Mitra episcopalis, 
a striking, scarlet-spotted, heavy shell, is abundant at the Philippine Islands, and 
occurs in Ceylon and in Polynesia. The animal is sluggish in its movements, and 
buries itself in the sand when the tide recedes. The mitras with simple lateral teeth 
are mostly ornamented with longitudinal ribs or plicae, and constitute the group 
Tarris. Some frequent coral-reefs, and others are found, often in considerable 
numbers, crawling upon the sands in sheltered and shallow bays. Over five hundred 
species of Mitridce are known. They abound in the islands of the Indian and Pacific 
Oceans, and seem to be scarcer on the shores of the great continents. They are 
not very numerous in the Atlantic, and even the tropical islands of the West Indies 
produce but an insignificant number, of unattractive form. Mitra zonata, found 
in deepish water off Italy and in a few T other parts of the Mediterranean, is a 
fine species, and one of the rarest of the family. A few species of Mitridce range as 
far north as Japan, and others occur at the Cape of Good Hope and New Zealand. 
The tulip-shells, forming the family Fasciolciriidce, are mostly fusiform (spindle- 
shaped), some having very long spires and anterior canals. They never have a 
thickened lip to the aperture, which is often grooved and striated within. The 
typical genus Fasciolaria and also Lcitirus exhibit oblique folds on the columella, 
a feature absent in the slender Fusus. All are furnished with a horny operculum. 
The radula has three rows of serrated teeth, the central tooth being narrow, and 
the laterals broad. Fasciolaria gigantea, from the coast of South Carolina, is one of 
the largest gastropods, attaining a length of 2 feet. In Leucozonia, a group of the 
genus Latirus, the outer lip of the shell has a more or less prominent spine-like tooth 
in front. In L. cingulata, from Panama, it is sometimes five-eighths of an inch in 
length, and although it appears as if it would be a hindrance to the animal when 
crawling, it doubtless serves some purpose in its economy. The allied family of 
the chank-shells ( Turbinellidce ) is not numerous in species, but contains several 
large and interesting forms. They are grouped together, on account of a similarity 
in dentition. The radula has three rows of teeth, the central tooth being nearly 
always three-pronged, and the laterals generally armed with a single or two 
unequal cusps. The typical species of Titrbinella have very solid, heavy, pear-shaped 
shells, covered with a thick, fibrous periostracum, and exhibit a few strong oblique 
folds on the columella. The T. scolymus, a West Indian form, is sometimes 18 
inches long. In India, Tiirbinella is largely used in the manufacture of carved 
bracelets, anklets, necklaces, and other ornaments. They are known under the 
name of chank-shells, and a fishery is carried on in the Gulf of Manaar. Occa¬ 
sionally sinistral examples are obtained, considered sacred by the Hindus, and also 
valued by the Buddhist priests of Ceylon and China. In Cynoclonta, another group 
