Oviparous

quadrupeds cover one another in the same way. That is to
say, in some cases the male mounts the female precisely as in the
viviparous animals, as is observed in both the land and the sea
tortoise....And these creatures have an organ in which the ducts
converge, and with which they perform the act of copulation, as is
also observed in the toad, the frog, and all other animals of the same
group.
Long animals devoid of feet, like serpents and muraenae,
intertwine in coition, belly to belly. And, in fact, serpents coil
round one another so tightly as to present the appearance of a
single serpent with a pair of heads. The same mode is followed by
the saurians; that is to say, they coil round one another in the act
of coition.