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PORPOISE (sometimes spelled Porpus an...

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Originally appearing in Volume V22, Page 106 of the 1911 Encyclopedia Britannica.
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PORPOISE (sometimes spelled Porpus and Porpesse) , a name derived from the O. Fr. porpeis, for See also:port-peis, i.e. See also:pig-See also:fish, See also:Lat. porcus, pig, and piscis, fish; the mod. Fr. marsouin is borrowed from the Ger. meerschwein, although the word is commonly used by sailors to designate all the smaller cetaceans, especially those numerous See also:species which naturalists See also:call " dolphins," it is properly restricted to the See also:common porpoise of the See also:British seas (Phocaena communis, or P. phocaena). The porpoise, when full grown, attains a length of 5 ft. or more; the dimensions of an adult See also:female specimen from the t~. -- See also:English Channel being: length from See also:nose to notch between the flukes of the tail, 624 in.; from the nose to the front edge of the dorsal fin, 29 in.; height of dorsal fin, 4i in.; length of See also:base of dorsal fin, 8 in.; length of See also:pectoral fin, g; in.; breadth of pectoral fin, 3i in.; breadth of tail flukes, 13 in. The See also:head is rounded in front, and differs from that of dolphins in not having the snout produced into a distinct " See also:beak " separated from the forehead by a groove. The under See also:jaw projects about See also:half an See also:inch beyond the upper.. The mouth is wide, bounded by stiff immobile. lips, and curves slightly upwards at the hinder end. The See also:eye is small, and the See also:external See also:ear represented by a See also:minute See also:aperture, scarcely larger than would be made by a See also:pin, about 2 in. behind . the eye. The dorsal fin, near the See also:middle of the back, is See also:low and triangular. The flippers are of moderate See also:size, and slightly sickle-shaped. The upper-parts are dark See also:grey or nearly See also:black according to the See also:light in which they are viewed and the See also:state of moisture or otherwise of the skin; the under-parts pure See also:white.

The See also:

line of demarcation between these See also:colours is not distinct, washes or splashes of grey encroaching upon the white on the sides, and varies some-what in different individuals. Usually it passes from the See also:throat (the anterior See also:part of which, with the whole. of the under jaw, is dark) above the origin of the flipper, along the middle of the flank, and descends again to the middle line 'before reaching the tail. Both sides of the flippers and flukes are black. The anterior edge of the dorsal fin is furnished with a See also:row of small rounded horny spines or, rather, tubercles, of variable number. One of the most characteristic anatomical distinctions between the porpoise and other members of the Delphinidae is the See also:form of the See also:teeth (numbering twenty-three to twenty-six on each See also:side of each jaw), which have See also:expanded, flattened, See also:spade-like crowns, with more or less marked See also:vertical grooves, giving a tendency to a bilobed or often trilobed form (fig. 2). The porpoise, which is sociable and gregarious, is usually seen in small herds, and frequents coasts, bays and estuaries rather than the open ocean. It is the commonest cetacean in the seas See also:round the British Isles, and not infrequently ascends the See also:Thames, having been seen as high as See also:Richmond; it has also been observed in the See also:Seine at Neuilly, near See also:Paris. It frequents the Scandinavian coasts, entering the Baltic in the summer; and is found as far See also:north as See also:Baffin's See also:Bay and as far See also:west as the coasts of the See also:United States. Southward its range is more limited than that of the See also:dolphin, as, though common on the See also:Atlantic coasts of See also:France, it is not known to enter the Mediterranean. It feeds on See also:mackerel, pilchards and See also:herrings and, following the shoals, is often caught by fishermen in the nets along with its See also:prey. In former times it was a common See also:article of See also:food in See also:England and France, but is now rarely if ever eaten, being valuable only for the oil obtained from its blubber.

Its skin is sometimes used for See also:

leather and See also:boot-thongs, but the so-called " porpoise-hides " are generally obtained from the See also:beluga. The Black See also:Sea porpoise (P. relicta) is a distinct species. A third species, from the See also:American See also:coast of the North Pacific, has been described under the name of Phocaena vomerina, and another from the mouth of the Rio de la See also:Plata as P. spinipennis. Nearly allied is Neophocaena phocaenoides, a small species from the See also:Indian Ocean and See also:Japan, with teeth of the same form as those of the porpoise, but fewer in number (eighteen to twenty on each side), of larger size, and more distinctly notched or lobed on the See also:free edge. It is distinguished from the common porpoise externally by its black See also:hue and the See also:absence of a dorsal fin. (See See also:CETACEA.) (R.

End of Article: PORPOISE (sometimes spelled Porpus and Porpesse)

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PORPHYRY (IlopcPisptos) (A.D. 233-c. 304)
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