Natural History of the Mammalia of India and Ceylon

Jerdon gives, on the authority of Blyth, another species, Platanista Indi, or the Indus porpoise, but Dr. Anderson has conclusively proved that this is identical with the Gangetic dolphin. The dentition of the soosoo is most curious. The perfect tooth in the young animal is sharp and pointed, but as the creature advances in age the fangs get broader, and the point wears down, till in old age the crown is so worn as to leave but a bony lump in its place.

GENUS ORCELLA—THE ROUND-HEADED RIVER DOLPHINS

The generic characteristics of these dolphins are, according to Dr. Anderson, as follows: "Head globular; dorsal fin low, situated behind the middle of the body; pectoral fins oval, about one-sixth the length of the animal; teeth conical, large, and fewer in the lower than in the upper jaw, thirteen to seventeen teeth in the upper and twelve to fourteen teeth in the lower jaw; skull beaked; beak broad at the base, anteriorly pointed; premaxillary not much laterally dilated, bearing one tooth; vertebræ sixty-two to sixty-three; first two cervical vertebræ ankylosed; lumbar transverse process moderately long; vertebræ ribs twelve to thirteen, with one or two free ribs; pelvic bones opposite thirty-fifth and thirty-sixth vertebræ."

These are the dolphins which were procured by Mr. Blyth in the Hooghly, and were supposed by him to be the young of the ca'ing whale (Globicephalus), which idea has also been adopted by Jerdon; but it has been since proved that the skeletons prepared from these supposed young whales are those of adults fully matured, and not of young animals, which have certain resemblances to Globicephalus as well as to the killer whales, Orca, from which the generic name has been derived, but yet was undoubtedly distinct. The killer whales have a very high dorsal fin in the middle of the back, with very large pectoral flippers as broad as long; in Orcella the back fin is low and behind the middle of the body, and the pectoral fin is only half as broad as long. In the ca'ing whale the back fin is more towards the shoulders, and the flippers are long and narrow; the genus Orcella in fact seems to be intermediate between the dolphin and the ca'ing whale, combining the head of Globicephalus with the body of Delphinus. Dr. Anderson, however, points out further differences than the external ones I have above alluded to. Orca, he says, is distinguished by a "more powerfully built skeleton, with considerably fewer vertebræ, there being only a maximum of fifty-three in it to a maximum of sixty-three in Orcella." In Orca generally four or five cervical vertebræ are ankylosed as in the cachelots, but in the two species of Orcella only the atlas and axis are joined. "In the killers and ca'ing whales the ribs are transferred to the transverse processes at the seventh dorsal, whilst in Orcella the transference does not take place until the eighth." The skull resembles that of Orca in the breadth of the upper jaw being produced by the maxillaries, whereas in Globicephalus this effect is caused by the premaxillaries. The teeth resemble the killer's.

As I have said so much about the killer whale, I may digress a little to explain what it is, though it is not a denizen of the Indian seas. It is to the Cetacea what the shark is to fishes—a voracious tyrant with a capacious mouth, armed with formidable teeth. It hesitates not to attack the largest sperm and Greenland whales, and the smaller whales, porpoises and seals will spring out of water and strand themselves on shore in terror at its approach. It ranges from twenty to thirty feet in length, and is of so gluttonous a character that in one recorded case a killer had been found choked in the attempt to swallow a fifteenth seal, the other fourteen, with thirteen porpoises, being found in its stomach!

According to Scammon three or four of them do not hesitate to grapple with the largest baleen whale; and, as described by Dr. Murie, "the latter often, paralysed through fear, lie helpless and at their mercy. The killers, like a pack of hounds, cluster about the animal's head, breach over it, seize it by the lips, and haul the bleeding monster underwater; and, should the victim open its mouth, they eat its tongue." In one instance he relates that a Californian grey whale and the young one were assaulted; the Orcas killed the latter, and sprang on the mother, tearing away large pieces of flesh, which they greedily devoured.

"These brutes have been known to attack a white-painted herring boat, mistaking it for a beluga; and it is stated that occasionally they will boldly lay siege to whales killed by the whalers, almost dragging them perforce under water. Near some of the Pacific sealing grounds they continually swim about, and swoop off the unwary young; even the large male sea-lions hastily retreat ashore and give these monsters a wide berth. The walrus also, with his powerful tusks, cannot keep the killers at bay, especially if young morses are in the herd. The cubs on such occasions will mount upon the mother's back for refuge, clinging for dear life, but the Orca, diving, comes suddenly up with a spiteful thud, and the cub, losing its balance, falls into the water, when in an instant it is seized by the remorseless whales." The speed of the killer whale is immense, as may be supposed when it can overtake the swift dolphins, which it catches and swallows alive. It has also been seen chasing salmon up the mouths of rivers.

The genus Orcella seems to come in between the sea and river dolphins, although Orcella fluminalis of Dr. Anderson is a purely fluviatile animal, which apparently never goes out to sea.

NO. 258. ORCELLA BREVIROSTRISThe Short-nosed Round-headed River Dolphin

HABITAT.—The estuaries of the Ganges and Brahmaputra rivers.

DESCRIPTION.—"The head is convex from the blow-hole to the upper lip, but its sides immediately below the angle of the mouth are somewhat anteriorly convergent, but rounded; the gape posteriorly has a long upward curve; the eye, which is well developed, is near the angle at the gape, and in the adult is placed about one inch above it, with a slightly downward slope; the ear is nearly on the same level as the angle of the mouth, but is extremely small, crescentic, and not measuring more than 0·12 inch in diameter. The posterior margin of the blow-hole is immediately behind the anterior angle of the eye; the blow-hole is crescentic and unsymmetrical, being more to the left than to the right side; there are two slight eminences about one inch behind the blow-hole; the construction of the neck occurs below the ear and slightly behind it" (Anderson's 'Anatomical and Zoological Researches,' p. 370). The other characteristics are triangular flippers half as broad as long. The back fin rises behind the centre of the back; it is comparatively small, falcate, curved over the top to a blunt point, and concave behind. The line of the back is sharp from this fin down to the tail. The ventral line is the same for some inches behind the anus. The colour is dark slaty-blue above, almost black, a little paler below, without any streaks or marks, such as in O. fluminalis and Risso's grampus.

SIZE.—From snout to caudal notch, about 7 feet.

I cannot find much on record concerning the habits of this dolphin, and my own acquaintance with it is too limited for me to afford much original information.

NO. 259. ORCELLA FLUMINALIS (Anderson)The Fresh-water Round-headed Dolphin

HABITAT.—The Irrawaddy river; Burmah.

DESCRIPTION.—This differs from the last in a "rather smaller, lower, and more falcate dorsal fin, its more pointed and less anteriorly bulging head, and rather shorter and broader pectoral fins" (Anderson). The colour is a pale bluish above, and white underneath, with numerous streaks, as in Risso's grampus.

SIZE.—From 7 to 7½ feet from snout to fork of tail.

Dr. Anderson, who has fully described this species, says that he has "never observed it in tidal waters, so that it is even more strictly fluviatile than the Gangetic dolphin. From a little below Prome to as far up as Bhamo, which is about 550 miles, as the crow flies, from the sea, these animals abound. It is asserted by the Shans of Upper Burmah that these dolphins are not to be found beyond a point thirty miles above Bhamo, where the course of the river is interrupted by rocks, and which they style Labine or Dolphin Point, from the circumstance that, according to them, it is the residence of certain Nâts, who there impose so heavy a toll on dolphins as to deter them from proceeding upwards."

This dolphin is somewhat like its marine cousins, being fond of gambolling round the river steamers. Solitary ones are seldom met with, usually two or three being together. When they rise to breathe the blow-hole is first seen; then, after respiration, the head goes down, and the back as far as the dorsal fin is seen, but rarely the tail flippers. They rise to breathe every 70 to 150 seconds, and the respiratory act is so rapid that it requires a very expert marksman to take aim and fire before the animal disappears.

Dr. Anderson says: "I have observed some of them disporting themselves in a way that has never yet been recorded of Cetacea, as far as I am aware. They swam with a rolling motion near the surface, with their heads half out of the water, and every now and then nearly fully exposed, when they ejected great volumes of water out of their mouths—generally straight before them; but sometimes nearly vertically. The sight of this curious habit at once recalled to me an incident in my voyage up the river, when I had been quite baffled to explain an exactly similar appearance seen at a distance, so that this remarkable habit would appear to be not uncommonly manifested. On one occasion I noticed an individual standing upright in the water, so much so that one-half of its pectoral fins was exposed, producing the appearance against the background as if the animal was supported on its flippers. It suddenly disappeared, and again, a little in advance of its former position, it bobbed up in the same attitude, and this it frequently repeated. The Shan boatmen who were with me seemed to connect these curious movements with the season—spring—in which the dolphins breed."

A similar thing has been noticed in the case of marine dolphins off the coast of Ceylon by Mr. E. W. H. Holdsworth, whose observations confirm the opinion of the Shan boatmen. (See 'P. Z. S.' 1872, p. 586.)

"The food of the Irrawady dolphin is apparently exclusively fish. The fishermen believe that the dolphin purposely draws fish to their nets, and each fishing village has its particular guardian dolphin, which receives a name common to all the fellows of his school, and it is this supposition that makes it so difficult to obtain specimens of this cetacean. Colonel Sladen has told me that suits are not unfrequently brought into the native courts to recover a share in the capture of fish in which a plaintiff's dolphin has been held to have filled the nets of a rival fisherman" (Anderson). This reminds me that in the surveying voyage of the Herald, as related by Mr. H. Lee, the natives of Moreton Bay entreated the seamen not to shoot their tame porpoises, which helped them in their fishing.

GENUS DELPHINUS—THE MARINE DOLPHINS

These are characterised by a convex forehead, with a protruding muzzle which forms a sort of beak; they have teeth in both jaws, numerous and conical, broad and high cranium, nasal passages vertical, no cæcum. They are gregarious in habit, carnivorous and extremely swift, but they must not be confounded with the dolphin of sailors, which is a true fish (Coryphæna hipparis) of great velocity and brilliant colours, which change like rainbow tints when the fish is dying. I have several times in vain tried to catch the fleeting shades with both oil and water-colours, but without success; for within a few minutes they change from the most vivid of greens and blues to a pale silvery grey. The true dolphin, of which we are treating, is the dolphin of the ancients, represented in all the old pictures and sculptures. They have a medium dorsal fin, and the pectoral flippers are about two-thirds longer than the breadth.

NO. 260. DELPHINUS PERNIGERThe Black Dolphin (Jerdon's No. 142)

HABITAT.—Bay of Bengal.

DESCRIPTION.—"Twenty-six teeth on each side above and below, obtuse, slightly curved inwards; of a uniform shining black above, beneath blackish."—Jerdon.

SIZE.—Total length, 5 feet 4 inches.

This species was taken in the Bay of Bengal and sent to the Asiatic Society's Museum by Sir Walter Elliot, but it does not appear to be mentioned by Professor Owen in his notice of the Indian Cetacea collected by Sir Walter Elliot.

NO. 261. DELPHINUS PLUMBEUSThe Lead-coloured Dolphin (Jerdon's No. 143)

HABITAT.—Malabar coast.

DESCRIPTION.—Thirty-six teeth in each side in the upper jaw and thirty-two in the lower jaw; of a uniform leaden colour, with the lower jaw white.

SIZE.—About 8 feet.

Whether this be the same as or a different species to the next I am unable to say, as the description is meagre, and the number of teeth vary so much in the same species that no definite rule can be laid down on them.

The following are the species named by Professor Owen and collected by Sir Walter Elliot.

NO. 262. DELPHINUS GADAMU

NATIVE NAME.—Gadamu.

HABITAT.—Madras coast.

DESCRIPTION.-Body fusiform, gaining its greatest diameter at the fore-part of the dorsal fin, decreasing forward to the head by straight converging lines, and with a gentle convex curve to the eyes and blow-hole; the forehead descends with a bold convex curve; the sides of the head converge from the eyes to the base of the snout, which is divided from the forehead by a transverse groove extending almost horizontally to the angles of the mouth, and it equals in length the distance from the base to the eyes, which is five inches and a-half; the lower jaw projects a little beyond the upper; the blow-hole is crescentic, in a line with the eyes, exactly in the middle of the head, with the horns of the crescent pointing towards the snout; the pectoral and dorsal fins are falcate and about equal in size; the colour is a dark plumbeous grey, almost black upon the fins, especially at their fore-part; the body below being of a pinkish ashy-grey, with a few small irregular patches of light plumbeous grey.

The dentition varies from 24—24/24—24 = 96, to 23—23/27—28 = 101, and 27—27/27—27 = 108.

SIZE.—About seven feet from snout to fork of tail; girth about 3 feet 9 inches.

NO. 263. DELPHINUS LENTIGINOSUSThe Freckled Dolphin

NATIVE NAME.—Bolla Gadimi, Telegu.

HABITAT.—Madras coast.

DESCRIPTION.—Body fusiform, as in the last, but with smaller pectoral and dorsal but larger caudal fin; the back is straighter and not so much rounded on the shoulders, and the colour is bluish-cinerous or slaty, freckled with small irregular spots of brown or plumbeous, and longitudinal streaks of the same flecked with white; the under parts a shade lighter than rest of the body. The snout is six inches in length.

Dentition: 32—32/32—33 = 129.

SIZE.—Seven to eight feet; girth four feet.

NO. 264. DELPHINUS MACULIVENTERSpot-bellied Dolphin

NATIVE NAME.—Suvva.

HABITAT.—Madras coast.

DESCRIPTION.—Forehead more convex than even D. gadamu, and head proportionately larger and body deeper. A deep shining plumbeous black on the upper part, becoming paler near the belly, which from the underpart of the jaw to the perineum is ashy-grey, with irregular spots and blotches.

Dentition: 27—27/30—30 = 114.

SIZE.—About seven feet.

NO. 265. DELPHINUS FUSIFORMISThe Spindle-shaped Dolphin

HABITAT.—Madras coast.

DESCRIPTION.—More slender in proportion to its length; a less elevated and less convex forehead than the last species; a proportionally thicker, broader, and more obtusely terminated snout; a deeper mandible or under jaw especially posteriorly, and smaller dorsal and pectoral fins, especially the latter. The greatest girth is in middle or fore-part of the dorsal fin, from which the body tapers to both ends, presenting the true spindle form. Colour plumbeous, lighter below, darkest on the fins and snout.

Dentition: 22—22/21—21 = 86 teeth.

SIZE.—About six feet.

NO. 266. DELPHINUS POMEEGRAThe Black or Pomeegra Dolphin

NATIVE NAME.—Pomeegra.

HABITAT.—Madras coast.

DESCRIPTION.—More slender than any of the foregoing species; longish snout, with 173 teeth, viz. 41—41/45—46. It is well to note the irregularity here, not only an odd number, but the lower jaw has the greater number, whereas it is generally the other way. Colour almost black, lighter beneath. Professor Owen's description is not so full as in other cases, but from the illustration it seems that the flukes of the caudal fin are longer, and the posterior edge of the dorsal straighter than in the others.

NO. 267. DELPHINUS LONGIROSTRISThe Long-snouted Dolphin

HABITAT.—Indian Ocean; coast of Ceylon.

DESCRIPTION.—Similar to the last, but with a longer and more slender snout.

NO. 268. DELPHINUS VELOX

This is also given by Dr. Kellaart as a species found on the coast of Ceylon.

Sir Walter Elliot mentions another species of dolphin, of which he had lost the drawing, about thirty-two inches long, of a uniform black colour, small mouth, and no dorsal fin, called by the Tamil fishermen Molagan.

GENUS PHOCÆNA—THE PORPOISES

No beak or rostrum; snout short and convex; numerous teeth in both jaws. Kellaart testifies to the existence of a true porpoise on the coasts of Ceylon—which he identifies with Phocæna communis—of a blackish colour above and whitish beneath.

GENUS GLOBICEPHALUS—THE CA'ING OR PILOT WHALE

Head globular in front; teeth few in number; the dorsal fin is high, situated nearer to the head than to the tail; the flippers very long and narrow; the fingers possessing an unusually large number of bones.

NO. 269. GLOBICEPHALUS INDICUSThe Indian Ca'ing Whale (Jerdon's No. 146)

HABITAT.—Bay of Bengal.

DESCRIPTION.—Body cylindrical, tapering to the tail; dorsal fin high, falcate, and placed about the middle of the body proper, excluding the tail portion; the forehead with a prominent boss over the snout, which is short; pectoral fins long and narrow; colour uniform leaden black, paler beneath.

SIZE.—Fourteen feet, flippers 2 feet; dorsal fin, 2¼ feet long, 11 inches high; tail flukes, 3 feet broad.

Blyth's specimens were procured in the Salt Lakes near Calcutta. It was for the young of this that he mistook Orcella brevirostris.

PHYSETERIDÆ—THE CACHELOTS OR SPERM WHALESGENUS EUPHYSETES NO. 270. PHYSETER or EUPHYSETES SIMUSThe Snub-nosed Cachelot

NATIVE NAME.—Wonga, Telugu.

HABITAT.—Bay of Bengal.

DESCRIPTION.—The general form of this animal resembles the porpoise, but the position of the mouth at once distinguishes it. It is small and situated, like that of the shark, considerably under the blunt rostrum, so much so as to lead one to conjecture whether or not it turns on its back in seizing its prey, as do the sharks. The blow hole is crescentic, but eccentrically placed to the left of the middle line of the head, and the horns of the crescent are turned diagonally backwards—that is to say, the lower limb points to the back whilst the upper one touches the middle line and points across; the eye is small; the pectoral fins are triangular, about one foot in length and four and a-half inches broad in the male, and four inches in the female; the dorsal fin is sub-falcate, standing about a foot high, and is nine to ten inches broad at the base, the male being the broader; the colour is a shining black above, paler and pinkish below.

Dentition: 1—1/9—9 = 20.

SIZE.—Six to seven feet.

The peculiarity of this cetacean is the preponderance of the cranial over the rostral part, more so, as Professor Owen remarks, than in any other species. The asymmetry of the bones too is remarkable, although this is characteristic of all the catodon whales, especially as regards the bones of the anterior narial passages, the left of which is very much larger than the right. This is also the case in the large sperm whale, but in Euphysetes the disproportion is still greater. In a notice on a New Zealand species (E. Pottsii), by Dr. Julius Haast, he gives the difference as fifteen times the size of the right aperture; the mouth is also peculiar from its position and small size, being very much overshot by the snout. It may, as Dr. Haast supposes, be a ground feeder, existing on the smaller hydroid zoophytes, otherwise it must, I think, turn on its side in seizing its prey.

MYSTICETE—WHALEBONE OR BALEEN WHALESGENUS BALÆNA—THE RIGHT WHALES

They are distinguished from the last group by their enormous heads, with more symmetrical skulls, the facial portion of which is greatly in excess of the cranial. The bones of the lower jaw are not united at the symphysis, but are held together by strong fibrous bands; the two rami are very much rounded and arched outwards; there are no teeth. The maxillary and premaxillary bones are much produced, forming a rostrum tapering, narrow, compressed and much arched in the right whales. From this depends the mass of whalebone, which grows from a fleshy substance "similar," as is aptly described by Dr. Murie, "to the roots of our finger-nails. It grows continuously from the roots like the latter, and in many respects corresponds, save that the free end is always fringed. Baleen, therefore, though varying from a few inches to a number of feet long, in fact approximates to a series of, so to say, mouth nail-plates, which laminæ have a somewhat transverse position to the cavity of the mouth, and thus their inner split edges and lower free ends cause the mouth to appear as a great hairy archway, shallower in front and deeper behind" (Cassell's Natural History).

The object of this vast amount of whalebone is to strain from the huge gulps of water the mollusca, &c., on which this animal feeds. The tongue of these whales is very large, filling up the space between the lower jaws. The gullet is small in comparison. The nasal aperture differs from the Denticete in being symmetrical, that is, having the double aperture, and in being directed forwards as in most mammals, instead of upwards and backwards as in the dolphins. The whale produces generally one at a birth, which it suckles for some length of time. The mammæ are pudendal. The right whales have no fin on the back; those that have form a separate genus, Balænoptera, i.e. fin-whales.

They are the most valuable of the cetacea, except perhaps the cachelot or sperm whale, as producing the greatest amount of oil and whalebone. Of the various species the most sought after is the Greenland or right whale (Balæna mysticetus), which ordinarily attains a length of fifty to sixty feet. An average whale between forty and fifty feet in length will yield from sixty to eighty barrels of oil and a thousand pounds of baleen.

Formerly all whaling vessels were sailers, but now powerful steamships are used, and the harpoon often gives way to the harpoon gun. A whale, when struck, will sometimes run out a mile of line before it comes up again, which is generally in about half an hour. The whalers judge as best they can, from the position of the line, in which direction he will rise, and get as near as possible so as to use the lance or drive in another harpoon. When killed, the animal is towed to the vessel and fastened on the port side, belly uppermost, and head towards the stern; it is then stripped of its blubber, the body being canted by tackles till all parts are cleared. The baleen is then cut out, and the carcase abandoned to the sharks, killer whales, and sea birds.

The baleen whales are not found in the intertropical seas. Of the known species there are the Greenland whale (B. mysticetus), the Biscay whale (B. Biscayensis), the Japan whale (B. Japonica), the Cape whale (B. australis), and the South Pacific whale (B. antipodarum).