The sea produces three different seals, which often ascend rivers from the coast, and can live in lagoons of fresh water; many cetaceans, besides the " right whale " and sperm whale; and the dugong, found on the northern shores, which yields a valuable medicinal oil.
In the southern and western islands the fauna is restricted mainly to foxes, bats, rats, mice, the sea otter, the penguin and other aquatic birds, and various cetaceans in the surrounding waters.
It must be admitted, however, that the links between Zeuglodon and typical cetaceans are at present unknown; but it may be hoped that these will be eventually brought to light from the deposits of the Mokattam Range, near Cairo.
Like most cetaceans it is gregarious and usually met with in "schools" or herds of fifteen or twenty individuals.
Meerschwein, although the word is commonly used by sailors to designate all the smaller cetaceans, especially those numerous species which naturalists call "dolphins," it is properly restricted to the common porpoise of the British' seas (Phocaena communis, or P. phocaena).