Chapter VI.

1. The fibres are between the sinews and the veins; but some of them are moistened with serum, and they extend from the sinews to the veins, and from the veins to the sinews. There is also another kind of fibre, which is produced in the blood of most, but not of all animals. When this is extracted from the blood, it does not coagulate, but if it is not taken out of the blood it coagulates. These fibres are present in the blood of most animals, but not in that of the stag, prox,[93] and bubalis,[94] and some others; so that their blood does not coagulate like that of other animals: the blood of stags is very like that of hares; for in both of these coagulation takes place; not firm, as in other animals, but trembling, like that of milk, if no coagulating substance is put into it. The blood of the bubalis coagulates more thickly, only a little less so than that of sheep. This is the nature of veins, sinews, and fibres.