late 83. 
MOLLUSCA. 
their beautiful, marbled shells. The shell, which at first closely resembles that of the snail 
and has a large aperture, becomes more and more elongated, the prominent spiral cor- 
rugations or whorls becoming more indistinct and sometimes disappearing almost entirely, 
while the aperture is transformed to a mere slit with serrated edges. The animal has a 
large head with long tentacles, while the portion of its body known as the Mantle is so 
large as to be able to cover the entire shell. The Cypraa burrow in the sand on the 
sea shore. They are very timid creatures and shun the light, and are found in all seas. 
1. The Cyprea Geographica is found in the southern seas. Its shell will be recognised 
as a favorite plaything of many of our juvenile readers. 
2. The Mitra Papalis is found in the Indian seas. The animal has a broad foot 
while its head terminates in a disproportionately long proboscis. 
3. The Voluta Undulata has a very broad foot and a large distinctly defined head 
with long tentacles. Both the shell and its occupant are of a yellow color with irregular 
streaks of a darker tint. It is only found on the shores of the southern seas. 
4. The Harpa Ventricosa is a beautiful variety with an eggshaped shell, voluted 
longitudinally. The animal has a small head and a very large foot, the length of which 
is more than twice that of the shell. The Harpa inhabits the Indian seas. 
5, The Nassa Coronata is found in every sea. The animal has a large flat head with 
two tentacles. Its foot is narrow and longer than the shell, and terminates in two tenta- 
cular appendages. 
6. The Strombus Pugilis is a very curiously fashioned creature. In addition to a 
long proboscis, the head bears two stout cylindrical tentacles, at the end of which the 
large and beautifully colored eyes are placed. The foot is as it were twisted round, the 
| formation of the foot does not allow of the animal’s creeping, its mode of progression 
being rather a jerk or jump. The outer edge of the shell is prolonged like a wing. The 
Strombi are indigenous to the tropical seas. 
animal has two long tentacles projecting from its head, and several other tentacular ap- 
pendages besides, while its foot bears a calcareous operculum. This genus is found in the 
Indian Ocean 
8. The Trochus Pagodus is met with in almost every sea, among the weed-grown rocks 
lining the coast. The animal has long tentacles, and a short fringed foot, with which it 
propels itself forwards by jerky steps. The beautifully fashioned, top-like shell is lined 
with mother of pearl. 
9. The Murex Palmatus is a beautiful specimen met with in the Southern seas. The 
excrescences on the shell assume every variety of shape, sometimes spinous, sometimes 
wart-like or corrugated. The animal has two tentacles placed close together, and a short 
foot with horny operculum. The genus to which this specimen belongs is remarkable for 
its yielding a peculiar coloring matter, from which the ancients used to prepare a purple 
dye. This matter is secreted by two glands situated near the gills, and is at first yellow in 
apart cs: On being exposed to the light however it soon changes to a violet, rather 
than a purple tint, of varying intensity. In the present day this dye is no longer employed, 
but in former ages it constituted an important and valuable article of commerce. 
10. The Pyrula Purpuracea contains a very curiously formed animal with a square 
foot and conical head, which is so completely covered by the mantle, as only to be seen 
on turning the creature over. The shell is thin and delicate, and very varied in form. This 
beautiful genus is found on the coasts of Central America. 
11. The Scalaria Preciosa has the whorls of its shell corrugated longitudinally. The 
animal has a small foot and a snout-like head with long tentacles. It is carnivorous in 
its habits, and secretes a purple coloring matter. 
12. The Chiton Priscus somewhat resembles the woodlouse in appearance, its shell, 
which consists of 8 plates overlapping one another like tiles, allowing the creature to roll 
itself together like a ball The edge of the mantle projects under the shell. The Chiton is 
a sluggish creature and is found in every sea. It adheres so tightly to the rocks, that 
it will allow itself to be pulled to pieces rather than be pulled off, and though generally 
found pe water, it can remain out of water for a length of time without being any the 
worse for it. 
The family of the Cyprea embraces a very large variety of form and coloring in | 
posterior part being prolonged and bearing a horny, crescent-shaped operculum. This | 
7. The Phasianella Bulimoides has a very beautifully marked, conical shell. The | 
