8 
MOLLUSCA. 
two sides, of the thickness of the back ; tlie sac, having no fins, re- 
seml)les an oval purse ; eight feet, all of which are about equal, very 
large in proportion to the body, and united at the base by a mem- 
brane ; they are employed by the animal in swimming, crawling, 
and seizing its prey. The length and strength of these limbs render 
them fearful weapons, which it twines round animals ; in this way it 
has even destroyed men while loathing. The eyes ai'e small in pro- 
portion, and the skin contracts over them so tightly as to cover them 
hollows of rocks. They are all carnivorous, living on crahs or any other marine 
animals whieh they are able to catch, the singular position of their arms greatly 
facilitating the necessity they are under of bringing their prey to their mouths, 
where the two strong mandibles enable them to break and cnish the hard bodies 
with which some of their food is covered. Some of them are entirely naked ; 
others live in a thin uniloeular shell, which envelopes them, and in which they float 
on the surface of the water ; and ther^e are others which have a multilocular shell, 
either completely or partially internal. 
First Division — Cephalopodes-polythalames.flmtnerghJ 
Testaceous Cephalopodes — Shell multilocular, enveloped completely, or only parti- 
ally enclosed in the posterior part of the animal’s body, often closely adheidng. 
Genus Belemnites... 
.... Orthocera . . 
.... Nodosaria . . 
.... Hippurites . . 
.... Conilites . . 
First Family. — Les Orthoc^^r^es 
.... Spirula . 
.... Spirolina 
.... Lituola . , 
^ Second Family,-— Les Lituol^es 
p Shell multilocular, with 
septa plain and sim- 
ple at the edges, the 
divisions of them not 
exhibiting any su- 
tures on the internal 
J thickness of the Sub- 
'S stance: shell straight 
or nearly so; not in 
a spiral form. The 
greater number of 
these shells are only 
known in a fossil 
L state. 
'■ Shell party in a spiral 
form, the whorls se- 
parated or connected 
wdth each other, the 
last continued in a 
right line. The sep- 
ta are generally tra- 
versed by a syphon, 
which in some spe- 
cies being continued 
in a straight line, 
V occasions the last 
one to have from 
three to six perfora- 
tions. The first ge- 
nus is known in a 
recent state only ; 
and Pdron has as- 
certained that the 
body of the animal 
is contained in the 
last septum only, and 
the shell enveloped 
by its posterior part. 
