8. They have also a proboscis, like that of the fly, and this organ is like a tongue. In the ceryx and the purpura this organ is hard, like that of the myops and œstrus, with which they pierce through the skins of quadrupeds; but this is more powerful in strength, for they can pierce through the shells of the baits. The stomach is joined quite closely to the mouth; the stomach of the cochlus is like the crop of a bird; below this there are two hard white substances like nipples, which also exist in the sepia, but are much harder. 9. From the stomach a long, simple intestine reaches as far as the spiral, which is on the extremity of the body. These are distinct, and in the purpura and the ceryx are in the helix of the shell. The bowel is continuous with the intestine. The intestine and bowels are joined together, and are quite simple, to the anus. The origin of the bowel is around the helix of the mecon,[130] and here it is wider. The mecon is, as it were, a superfluous part in all testacea, afterwards another bend causes it to return to the fleshy part; the end of the entrail, where the fæces are emitted, is near the head, and is alike in all turbinated shells, whether terrestrial or marine. [130] The so-called liver (_Strack_). Papaver (_Scaliger_). 10. In the larger cochli a long white passage, contained in a membrane, and in colour resembling the upper mastoid appendages, is joined from the stomach to the œsophagus, and it is divided into segments like the ovum of the carabus, except that it is white, while the other is red. It has neither exit nor passage, but it is contained in a thin membrane, which has a narrow cavity. From the intestine black and rough bodies descend continuously, like those in the tortoise, but they are less black. 11. Both these and white bodies occur in the marine cochli, but they are less in the smaller kinds. The univalves and bivalves are in some respects like these, and in others they are different, for they have a head, horns, and mouth, and something like a tongue, though in smaller species these are inconspicuous from their minute size, and they are not discernible when the animals are dead or at rest. They all contain the mecon, but not in the same position, nor of the same size, nor equally conspicuous. In the lepas it is in the bottom of the shell, in the bivalves near the hinge. 12. They all have hair-like appendages placed in a circle, and so have the pectens, and that which is called the ovarium in those that have it; where it is possessed, it is placed in a circle on the other side of the circumference, like the white portion in the cochli, for this is alike in all. All these parts, as I have said, are conspicuous in the larger kinds, but in smaller not at all, or scarcely so, wherefore they are most conspicuous in the larger pectens, and these have one valve flat like an operculum.