1. We have hitherto treated of sanguineous animals, the parts possessed by all as well as those which are peculiar to each class, and of their heterogeneous and homogeneous, their external and internal parts. We are now about to treat of ex-sanguineous animals. There are many classes of these, first of all the mollusca.[99] These are ex-sanguineous animals, which have their fleshy parts external, and their hard parts internal, like sanguineous animals, as the whole tribe of cuttle-fish. Next the malacostraca, these are animals which have their hard parts external, and their interior parts soft and fleshy; their hard parts are rather liable to contusion than brittle, as the class of carabi and cancri. [99] The Cephalopoda. 2. Another class is that of the testacea. These are animals which have their internal parts fleshy, and their external parts hard, brittle, and fragile, but not liable to contusion. Snails and oysters are instances of this class. 3. The fourth class is that of insects, which includes many dissimilar forms. Insects are animals which, as their name signifies, are insected either in their lower or upper part, or in both; they have neither distinct flesh nor bone, but something between both, for their body is equally hard internally and externally. There are apterous insects, as the julus and scolopendra; and winged, as the bee, cockchafer, and wasp; and in some kinds there are both winged and apterous insects; ants, for example, are both winged and apterous, and so is the glowworm. 4. These are the parts of animals of the class mollusca (malacia); first the feet, as they are called, next to these the head, continuous with them; the third part is the abdomen, which contains the viscera. Some persons, speaking incorrectly, call this the head. The fins are placed in a circle round this abdomen. It happens in many of the malacia that the head is placed between the feet and the abdomen. 5. All the polypi, except one kind, have eight feet, with a double row of suckers. The sepia,[100] teuthis,[101] and teuthos[102] possess as a characteristic part two long proboscidiform members, which have rough suckers at their extremities, with which they seize their food and bring it to their mouth; and when a storm arises they weather it out, fastening these members upon a rock, like an anchor. They swim by means of the fin-like members which are attached to the abdomen. There are suckers upon all their feet. [100] Sepia officinalis. [101] Loligo vulgaris (_Owen_). [102] Loligo media (_Owen_).