Page:The American Cyclopædia (1879) Volume VI.djvu/201

 DOLPHIN 193 (Bon.) has an obtuse, conical, and rounded head, without prominent beak, and without dorsal fin. The whitefish, or white whale (B. borea- lis, Less.), is a beautiful cream-white dolphin, symmetrical, and very swift ; the length varies Jroin 12 to 20 ft. ; the teeth, according to Cu- vier, are f:f ; being well covered with fat, it is sometimes chased by coast whalers, especially about the mouths of rivers, where it feeds upon the cod, haddock, flounder, and other fish ; it is essentially arctic, though it descends to the tem- perate regions of both hemispheres ; it has been seen in the river St. Lawrence as high up as Que- bec. The genus globicephalus (Less.) includes the D. gloliceps((jr?.), commonly called the de- ductor, social, bottle-head, blackfisb, or howling whale ; it resembles the beluga in the shape of the head, but differs from it in having a dorsal fin ; the length is from 16 to 24 ft., and the general color a shining jet-black ; the teeth are from 20 to 28 in each jaw ; its favorite resort is the northern temperate ocean in both hemi- spheres ; it is included by De Kay in the fauna of New York ; it herds in great numbers, ap- parently following a leader, and is easily driven streams and lakes, even to the foot of the An- des ; the beak is long, but cylindrical, bristled round with strong hairs, and obtuse at the end ; the teeth are about 134, resembling incisors in Deductor (Globicephalus melas). upon beaches; the proper name is cjlobicepha- lus melas (Less.). Some species of the genus have been found in the Mediterranean. The long-beaked dolphins (delphinorhynclius, La- ce^.) have a prolonged snout, thyi and narrow, not separated from the cranium by a furrow ; the straight jaws are furnished with numerous sharp teeth, and the dorsal fin is single; some of the species attain the length of 36 ft. The best known, D. micropterus, Guv., or D, Sow- erbyi, Desm., is remarkable for the snout be- ing four times the length of the cranium, and for the curvature upward and forward of the posterior part of the intermaxillaries, carrying with them the maxillaries, frontals, and occi- pital; it is a northern species, and has been found stranded on the French and English coasts. There are two remarkable genera of fresh-water dolphins, one of which, the dol- phin of the Ganges (platanista Gangetica, Gray.), will be described under Soosoo, the Bengalee name. The other is the Bolivian dol- phin (inia Boliviensis, D'Orb.), found in the tributaries of the Amazon and the neighboring Bolivian Dolphin (Inia Boliviensis). front and molars behind ; the body is short and slender, the pectorals large, the dorsal small and behind the middle of the back ; the skin is fine and smooth ; the average length of the adult is about 7 ft. ; the color varies from pale blue to blackish above, and is rosy beneath. It comes frequently to the surface, and is com- paratively slow in its movements; its food con- sists almost entirely of fish, which are devoured with the snout above water ; it is killed by the natives for its oil. This curious animal seems to form an intermediate type between the car- nivorous and the herbivorous or sirenoid ceta- ceans. The delphinidw are of little value to the whaler, as they are difficult to catch, and their covering of fat is much less than in the whales. Near the mouths of rivers and on the coasts herds of them are occasionally hunt- ed with profit for their oil and their skins, and in high northern regions even for food. Many genera of delphinidce inhabited the seas during the tertiary epoch, some very like the present dolphins, others very different from them. Their fossil remains are found abundantly in the miocene,' pliocene, and diluvial strata of America and Europe. The name of dolphin was long ago given by Dutch navigators to a scomberoid fish of the genus coryphcena (Linn.), inhabiting the Mediterranean and the seas of warm and temperate regions. The genus has no detached finlets, no isolated dorsal spines, and no armature on the tail ; the body is mod- erately long, more or less compressed, and cov- ered with small scales ; there is a single dorsal fin, with flexible rays, extending from the head to near the caudal ; the ventrals are thoracic. The generic name is derived from nopv^r/, sum- mit, in reference to the elevated shape given to the forehead by a bony crest of the inter- parietal and frontal which rises between the intermaxillaries and extends to the occiput; this gives a trenchant aspect to the head, with a very convex facial profile ; the eyes conse- quently seem low. The mouth is large, having card-like teeth on the jaws and palatal bones. The dolphin of the Mediterranean, so famous for the beauty of its colors when dying, is the 0. hippurus (Linn.). Many writers have fol- lowed the Dutch error as to the name of this