galeos however chases the sting-ray, and also indeed other fishes, but the sting-ray in particular, just as on land the weasel chases serpents, so great is its greed for the very poison itself. Those however stung by the sting-ray find good treatment in the galeos, as well as in red mullet and laser.
XIII. Equally remarkable is the might of Nature in those creatures also which are amphibious, such as the beaver, which they call castor and its testes castoreum. Sextius, a very careful inquirer into medical subjects, denies that the beaver himself bites off his own testes when it is being captured; he says that on the contrary these are small, tightly knit, attached to the spine, and not to be taken away without destroying the creature’s life. Castoreum (beaver-oil) he says is however adulterated by beaver’s kidneys, which are large, while the real testes are found to be very small. Moreover, they cannot even be the creature’s bladders, for they are twin, and no animal has two bladders. In these pouches (he goes on) is found a liquid, which is preserved in salt. Accordingly one of the tests of fraud is whether two pouches hang down from one connection, while the liquid itself is adulterated by adding to it cummin and beaver blood or ammoniacum, because the testes ought to be of the colour of ammoniacum, coated with a liquid like waxy honey, with a strong smell, a bitter taste, and friable. The most efficacious castoreum comesa from Pontus and Galatia, the next best from Africa. Doctors cause sneezing by its smell. It is soporific if the head is rubbed all over with beaver oil, rose oil, and peucedanum, or if by itself it is taken in water, for which reason it is useful in brain fever. It also arouses, by