Genera: Monodon, Balaena, Physeter, Delphinus.
SPERM -Whale, or Cachalot (Physeter macrocephalus), the largest representative of the toothed whales, its length and bulk being about equal to, or somewhat exceeding those of the Arctic right-whale, from which, however, it is very different has on each side from twenty to twenty-five stout conical teeth,.
SPEUSIPPUS (4th century B.C.), Greek philosopher, son of Eurymedon and Potone, sister of Plato, is supposed to have been born about 407 B.C. He was bred in the school of Isocrates; The Sperm-Whale (Physeter macrocephalus).