middle of November

and the middle of December; as also the sargue,
and the smyxon or myxon, and the cephalus; and their period of
gestation is thirty days. And, by the way, some of the grey mullet
species are not produced from copulation, but grow spontaneously
from mud and sand.

As a general rule, then, fishes are in roe in the spring-time;
while some, as has been said, are so in summer, in autumn, or in
winter. But whereas the impregnation in the spring-time follows a
general law, impregnation in the other seasons does not follow the
same rule either throughout or within the limits of one genus; and,
further, conception in these variant seasons is not so prolific.
And, indeed, we must bear this in mind, that just as with plants and
quadrupeds diversity of locality has much to do not only with
general physical health but also with the comparative frequency of
sexual intercourse and generation, so also with regard to fishes
locality of itself has much to do not only in regard to the size and
vigour of the creature, but also in regard to its parturition and
its copulations, causing the same species to breed oftener in one
place and seldomer in another.