National Geographic : 1940 Jan
WHALES, GIANTS OF THE SEA 83 Fishermen say that the very young calf swims a little ahead of its mother and that it is pushed to the surface each time she rises to breathe. Along the Hatteras coast, Bottle nose Dolphins feed on squeteague, or weakfish, and elsewhere on various shoal fish. Ganges River Dolphin, or Susu (Platanista gangetica) The distinguishing features of this dolphin are the long, slender, compressed beak with its formidable array of teeth, wedge-shaped fore head, small, degenerate, lensless eyes, longi tudinal slitlike blowhole, distinctly constricted neck, low, ridgelike dorsal fin, and broad flip pers cut off squarely at their ends (Plate XVIII). The inoffensive Susu may remain at the bot tom of a river probing about in the mud for two minutes. Being almost blind, it must be guided to its food by the sense of touch in its long snout. Irrawaddy River Porpoise (Orcella brevirostris) This beakless porpoise is an inhabitant of the warmer Asiatic coastal waters (Plate XVIII). Its geographic range extends from the mouths of the Ganges through the Strait of Malacca to Borneo on the China Sea and northward into the Gulf of Siam. Schools travel up the Irrawaddy River more than 900 miles from salt water. In India the oil from the blubber is rubbed on externally as a remedy for rheumatism. Burmese fishermen along the Irrawaddy River believe that this porpoise purposely leads fish into their nets. The Irrawaddy Porpoise is slate blue above and lighter below. Males reach a length of at least 7'~2 feet. There is a rounded fore head that curves regularly from the upper lip to the blowhole, moderately long and broad triangular flippers, and the dorsal fin is located behind the middle of the animal's length, with a low dorsal ridge back of it. This porpoise rises to breathe at intervals varying from 70 to 150 seconds, emitting each time a short blowing noise. It has a habit of squirting water from its mouth, generally straight ahead, but sometimes upward. Long-snouted Dolphin (Stenella plagiodon) Schools of Long-snouted Dolphins are often seen by passengers on the coastwise steamships that pass within sight of the Diamond Shoal Lightship near Hatteras. North Carolina (Plate XIX). From a distance these dolphins appear 'hotograph by Maynard Owen Williams very dark, almost black, above and paler HORN OF TIIE "SEA UNICORN" beneath. At closer range the white spots on This tusk is about eight feet long and was taken the purplish-gray upper parts are conspicuous, from a Narwhal killed by Eskimos in a fjord near and as the dolphin rolls at the surface the Godthaab, Greenland (Plate XXIV).