1. Animals also differ in being in good condition or not during gestation. The testacea, as the pectens and the malacostraca, as the carabi and such like, are best when pregnant; for this word is also used of the testacea. For the malacostraca have been observed both in the act of copulation and oviposition; but none of the testacea have ever been seen so occupied. The malacia, such as the teuthis, sepia, and polypus, are most excellent when pregnant; and almost all fish are good during the early part of the period; but as the time advances some are good and some not so. 2. The mænis thrives during gestation. The form of the female is round, that of the male longer and broader. And when the period of gestation commences in the females, the males become black and variegated, and are not fit to eat. Some persons call them tragi at this period. Those which are called cottyphus and cichla also change their colour; and the caris also changes at this season and some birds, which are black in spring and afterwards become white. 3. The phycis also changes its colour; for it is white at all other seasons, and variegated in the spring. This is the only sea fish that, as they say, makes a nest in which it deposits its ova. The mænis, as it was before observed, and the smaris also change their colours, and from being white in summer become black. This is particularly conspicuous about the fins and gills. The coracinus is best when pregnant, and so is the mænis. The cestreus, labrax, and nearly all creatures that swim are inferior at this season. 4. There are a few which are good, whether pregnant or not, as the glaucus. Old fish also are inferior; and old tunnies are not even fit for salting, for much of the flesh is dissolved. The same thing also happens with other fish. The older fish are distinguished by the size and hardness of their scales; an old tunny has been taken which weighed fifteen talents, and the length of the tail was two cubits and a span. 5. River and pond fish are most excellent, after depositing their ova and semen, and recovering their flesh. Some of them, however, are good while pregnant, as the saperdis; and others bad, as the glanis. In all the male is better than the female; but the female glanis is better than the male. Those which they call female eels are better than the males. They call them females, though they are not so, but only differ in appearance. BOOK THE NINTH. CHAPTER I. 1. The dispositions of obscure and short-lived animals are less easily observed than those of long-lived animals; for they appear to have a certain inclination towards each natural affection of the soul, such as prudence and folly, courage and cowardice, mildness and cruelty, and such other habits. Some also, which have the sense of hearing, appear to be capable of a certain degree of instruction and discipline, both from one another and from mankind, for they not only distinguish the difference of sounds but also of signs.