ORDER RODENTIA.

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 toGlobicephalusas 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; inOrcellathe 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 genusOrcellain fact seems to be intermediate between the dolphin and the ca'ing whale, combining the head ofGlobicephaluswith the body ofDelphinus. 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 inOrcella." InOrcagenerally four or five cervical vertebræ are ankylosed as in the cachelots, but in the two species ofOrcellaonly 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 inOrcellathe transference does not take place until the eighth." The skull resembles that ofOrcain the breadth of the upper jaw being produced by the maxillaries, whereas inGlobicephalusthis 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 afifteenthseal, 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; theOrcaskilled 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 theOrca, 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 genusOrcellaseems to come in between the sea and river dolphins, althoughOrcella fluminalisof Dr. Anderson is a purely fluviatile animal, which apparently never goes out to sea.

NO. 258. ORCELLA BREVIROSTRIS.The 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 inO. fluminalisand 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 styleLabineor Dolphin Point, from the circumstance that, according to them, it is the residence of certainNâts, 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 ofCetacea, 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 theHerald, 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 PERNIGER.The 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 PLUMBEUS.The 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.

NATIVENAME.—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 LENTIGINOSUS.The Freckled Dolphin.

NATIVENAME.—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 MACULIVENTER.Spot-bellied Dolphin.

NATIVENAME.—Suvva.

HABITAT.—Madras coast.

DESCRIPTION.—Forehead more convex than evenD. 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 FUSIFORMIS.The 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 POMEEGRA.The Black or Pomeegra Dolphin.

NATIVENAME.—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 LONGIROSTRIS.The 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 fishermenMolagan.

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 withPhocæna 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. GLOBICEPHALUSINDICUS.The 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 mistookOrcella brevirostris.

PHYSETERIDÆ—THE CACHELOTS OR SPERM WHALES.

GENUS EUPHYSETES.

NO. 270. PHYSETERorEUPHYSETES SIMUS.The Snub-nosed Cachelot.

NATIVENAME.—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 inEuphysetesthe 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 WHALES.

GENUS 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 theDenticetein 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).

GENUS BALÆNOPTERA—FINBACK WHALES OR RORQUALS.

Are distinguished by their longer and narrower bodies, smaller heads, being one-fourth instead of one-third the length of the body, smaller mouths, shorter baleen, plaited throats, and smaller flippers; they have a dorsal fin behind the middle of the back, and the root of the tail is compressed laterally. They also present certain osteological differences from the right whales; the latter have the whole of the seven cervical vertebræ anchylosed, that is to say generally, for sometimes the seventh is free. In the finbacks the cervical vertebræ are, as a rule, all distinct and free, although occasionally anchylosis may take place between two or more of them. The sternum of theBalænaconsists of a broad, flattened, heart-shaped or oval presternum. "In the fin whales (Balænoptera) it is transversely oval or trilobate, with a projecting backward xiphoid process" (Professor Flower). The ulna and radius in the rorquals are also comparatively longer than in the baleen whales. In the skull, the supraorbital processes of the frontals are broader in the rorquals than in others, and the olfactory fossa is less elongated.

They are more muscular and active animals than the right whales, and have a less amount of blubber and much shorter whalebone, consequently are not so much sought after by whalers, as the risk in attacking them is not compensated for by the commercial results. Many of them grow to enormous size, far exceeding any of the baleen whales. The common rorqual, razorback, or pike-whale of the English coasts (B. musculus) attains a length of seventy feet; it is black above and pure white below. The sulphur-bottom whale (B. sulfureus) is known by its yellowish belly, and with Sibbald's whale (B. Sibbaldii) grows to a length of one hundred feet, to which size our Indian species also approaches.

NO. 271. BALÆNOPTERAINDICA.The Indian Rorqual(Jerdon's No. 147).

HABITAT.—The Indian Ocean.

DESCRIPTION.—External characteristics those of the genus, but from Mr. Blyth's observations the lower jaw of this species is more slender in proportion to its size than that of any other rorqual or even right whale.

SIZE.—Up to 90 and possibly 100 feet.

There is a most interesting article on the great rorqual of the Indian Ocean by Mr. Blyth in the 'Journal of the Asiatic Society' for 1859, p. 481. He notices that the existence of great whales was known to and recorded by the ancients. Nearchus, the commander of Alexander's fleet, which sailed from the Indus to the Persian Gulf inB.C.327, mentions having met with them, and that on the coast of Mekran the people constructed houses of the bones of stranded whales. In modern times an occasional one gets on shore, as was the case with one at Chittagong in 1842, another on the Arakan coast in 1851. In 1858 one of 90 feet was stranded at Quilon on the west coast, as reported by the Rev. H. Baker of Aleppi, who also mentions that one, said to be 100 feet long, was cast ashore some years previously. He writes to Mr. Blyth: "Whales are very common on the coast. American ships, and occasionally a Swedish one, call at Cochin for stores during their cruises for them; but no English whalers ever come here that I have heard of."

I wonder at any whaling vessel coming out of their way after this species, for I have always heard from whalers that the finback is not worth hunting. It is possible that in cruising after sperms they may go a little out of their way to take a finback or two. However, to return to Blyth's remarks. Of the whale stranded on the Arakan coast a few bones were sent to the Society's Museum in Calcutta; they consisted of the two rami of the lower jaw, measuring 20 feet 10 inches, a right rib, the left radius, and five vertebræ, which are now to be seen at the Indian Museum. He writes as follows on them: "The proportional length of the radius indicates the animal to have been a Balænoptera or rorqual, while the remarkable slenderness of the lower jaw suffices to prove it a distinct species from any hitherto-described rorqual."

The finback does not confine itself entirely, or even chiefly, as stated by Blyth, to a diet ofCephalapoda, but is a fish-eater to boot, doing great damage to shoals of such fish as cod, herrings, &c., as many as six to eight hundred fish having been found in the stomach of one.

They are not particularly shy, and will sometimes follow a vessel closely for days. I read not very long ago an account in one of the Indian newspapers of a steamer running over one of these animals, and nearly cutting it in two; the agony of the poor brute as he struggled in the water, vainly trying to sound, was graphically described. A similar adventure occurred some years ago to the B.I.S.N. Company's steamerEuphrates, on a voyage from Kurrachee to Bombay, when about sixty miles from the latter place. The captain writes: "It appears that the animal had for about half an hour amused itself by crossing and recrossing the bow, and then at last suddenly turned and came straight for the vessel, striking us about ten feet from the stem. It struck with such force as to send a considerable quantity of spray on deck. The only other instance that has occurred here lately was in the case of the S.S.Dalhousie, when about twelve miles from Kurrachee; it was in September of last year, and the Bombay papers had a full account of it at the time." I am indebted to my friend Mr. M. C. Turner for this and some other interesting letters on this subject. Captain A. Stiffe, of the late Indian Navy, writes regarding the drowning of a whale by entanglement with a submarine cable, off the coast of Mekran: "The telegraph cable was broken, and a dead whale hove up to the surface, with three turns of cable round the neck of his tail, by which he was drowned. I had the three turns in my office at Kurrachee, and there they are now I dare say. I don't remember any more details. There are always shoals of whales about that part, and it is supposed a 'bight' of the cable lying off the ground got wound up like a rope round a screw." I myself was in a sailing vessel going about five or six knots, when a whale played about for a time, and then rose and spouted just under the bow, covering the forecastle with spray. The captain, who was standing by me, quite expected a shock, and exclaimed—"Look out! hold on!"

SIRENIA—THE MANATEES.

This group contains thephytophagousorherbivorouscetacea. Their teeth have flat crowns, and they live on aquatic vegetation, though, according to Cuvier, they sometimes leave the water for pasture on shore, but this has not been authenticated, and is probably a mistake. The other characteristics of the group are pectoral mammæ and hairy moustaches. The anterior narial aperture in the skull opens upwards, but the orifices of the nostrils are placed at the end of the muzzle. The stomach is complex, being divided into four sacs, and they have a large cæcum. The flippers are broad, and the animal uses them with some dexterity in supporting its young in the act of suckling. As at such times they frequently raise the upper part of the body out of water, they have given rise to the ancient fables regarding mermaids and sirens. There is something human-like, although repulsive, in the aspect of these creatures, especially in the erect attitude just alluded to. No wonder the ancient mariners, with their restricted knowledge and inclination to the marvellous, should have created the fabulous mermaid, half-fish and half-woman, and have peopled the rocks and seas of Ceylon with seductive sirens with imaginary flowing tresses and sweet ensnaring voices. As regards the latter it may be that the strange phenomena related by Sir Emerson Tennent, of musical sounds ascending from the bottom of the sea, and ascribed by him to certain shell-fish, gave rise to the mermaid's song. Sir Emerson's account has in itself a touch of the romantic and marvellous. He says: "On coming to the point mentioned I distinctly heard the sounds in question. They came up from the water like the gentle thrills of a musical chord, or the faint vibrations of a wineglass when its rim is rubbed by a moistened finger. It was not one sustained note, but a multitude of tiny sounds, each clear and distinct in itself, the sweetest treble mingling with the lowest bass. On applying the ear to the wood-work of the boat the vibration was greatly increased in volume." Similar sounds have been heard elsewhere in the Indian seas, and doubtless the ancients connected this mysterious music of the ocean with the animals round which they had thrown such a halo of romance. But to return to the prose of the subject. The Sirenia consists of the Manatees (Manatus), the Dugongs (Halicore), and the Stellerines (Rhytina); the latter is almost extinct; it used to be found in numbers in Behring Straits, but was exterminated by sailors and others, who found it very good eating. The Manatee inhabits the African and American coasts, along the west coast of the former continent, and in the bays, inlets, and rivers of tropical America, but the one with which we have to do is the dugong or halicore, of which the distribution is rather widespread, from the Red Sea and East African coasts to the west coast of Australia. The latter country possesses an organised dugong fishery, which bids fair to exterminate this harmless animal. They are prized for the excellent quality of the oil they yield, which is clear and free from objectionable smell.

GENUS HALICORE—THE DUGONG.

Have grinders of two cones laterally united. The premaxillary region is elongated and bent downwards, overlapping the very deep lower jaw, which is similarly bent down. They have ordinarily two incisors in the upper jaw, none in the lower. No canines, and molars 3—3/3—3, total fourteen teeth. The incisor tusks in the bent-down upper jaw are longer in the male, and sometimes project beyond the thick fleshy lips, but in the female they are small. The head is round, the lips thick and bristled with moustaches, the body is elongated, and the tail terminated by a crescent-shaped flapper.

NO. 272. HALICORE DUGONG.The Dugong. (Jerdon's No. 240).

NATIVENAME.—Mooda Oora, Singhalese.

HABITAT.—Indian Ocean off Ceylon.

DESCRIPTION.—Body pisciform, terminated by a horizontal fin with two lobes; colour slaty brown above, sometimes bluish black, whitish below.

SIZE.—From 5 to 7 feet long usually, but said to reach 10.

Dr. Kellaart says that at an early age this animal has as many as 32 teeth, viz. inc. 4/8, and molars 5—5/5—5, but when adult there are only 14, as mentioned above. The molars, according to Dr. Murie, succeed each other, the fore ones dropping out, and others from behind taking their places. It feeds on fucus and other seaweeds, and the flesh is considered good eating, and not unlike veal or, some say, pork. They are lethargic in disposition, and in those countries where they have been unmolested they are so fearless of man as to allow themselves to be handled—a confidence somewhat betrayed by the natives, who on such occasions manage to abstract the fattest calves, which are considered a delicacy.

ORDER RODENTIA.

THE GNAWERS.

This order, GLIRESof Linnæus and his followers, is composed of animals, chiefly of small size, which differ from all others by the peculiarity of their teeth. No one, even though he be most ignorant of comparative anatomy, could mistake the rat or rabbit-like skull of a rodent for that of any other creature. The peculiar pincer-like form of the jaws, with their curved chisel-shaped teeth in front, mark the order at a glance. There is no complexity in their dentition. There are the cutters or incisors, and the grinders; and of the cutters there are never more than two in each jaw, that is to say efficient and visible teeth, for there are in some species rudimentary incisors, especially in the young, but these either disappear or take no part in work. Between the grinders and incisors are toothless gaps. The formation and growth of the teeth are peculiar; and it is strange that the gigantic elephant should be the nearest approach to these small creatures in this respect. The teeth—in most cases the grinders, but always the incisors—grow continuously from a persistent pulp, and therefore loss from attrition is kept constantly supplied by growth from behind. The incisors are planted in a socket which is the segment of a circle. These segments are not equal in both jaws. The lower one is a small segment of a large circle, the upper one is the reverse, being a larger segment of a smaller circle. The angle at which they meet is always the same. Some curious malformations are occasionally found which illustrate the growth of these teeth. Should by any chance, accident or design, one of these incisors get diverted from its proper angle and not meet with the friction which is necessary to keep it in its normal condition, it goes on growing and growing, following its natural curve till it forms a ring, or by penetrating the mouth interferes with the animal's feeding. A case is recorded by Blyth of a rat which had an eye destroyed by a tooth growing into it. Here again occurs a similarity to the elephant, whose tusks grow in the same manner, and if abnormally deflected will occasion, as in the case of one lately described to me, serious hindrance to the movement of the trunk. The incisors of rodents are composed of dentine coated in front with a layer of hard enamel, the other surfaces being without this protection, except in the case of some, amongst which are the hares and rabbits, which have a thin coating as well all over. These forms are those with rudimentary incisors, and constitute the links connecting the other mammalia with the Gnawers.

The molars are much alike in structure, and can hardly be divided, as they are by some naturalists, into molars and premolars. They take the three hindmost as molars, regarding the others as premolars. Sometimes these grinders have roots, but are more commonly open at the end and grow from a permanent pulp. They are composed of tubular and convoluted portions of enamel filed up with dentine, and their worn surfaces show a variety of patterns, as in the case of the Proboscidea. These enamelled eminences are always transverse, and according to Cuvier those genera in which these eminences are simple lines, and the crown is very flat, are more exclusively frugivorous; others, in which the teeth are divided into blunt tubercles, are omnivorous; whilst some few, which have no points, more readily attack either animals, and approximate somewhat to the Carnivora.

The head is small in proportion to the body, the skull being long and flat above; the nasal bones are elongated; the premaxillaries very large on account of the size of the incisor teeth, and the maxillaries are, therefore, pushed back; the zygomatic arch is well developed in most, but is in general weak; the orbit of the eye is never closed behind; the tympanic bulla is very large; the jaw is articulated in a singular manner; instead of the lateral and semi-rotary action of the Herbivora, or the vertical cutting one of the flesh-eating mammals, the rodent has a longitudinal motion given by the arrangement of the lower jaw, the condyle of which is not transverse, but parallel with the median line of the skull, and the glenoid fossa, or cavity into which it fits, and which is situated on the under side of the posterior root of the zygoma, is so open in front as to allow of a backwards and forwards sliding action. The vertebral column is remarkable for the great transverse processes directed downwards, forwards, and widening at the ends. In the hare these processes are largely developed; the metapophyses or larger projections on each side of the central spinous process are very long, projecting upwards and forwards; the anapophyses or smaller projection in rear of the above are small; and the hypapophyses or downward processes are remarkably long, single and compressed; according to Professor Flower these latter are not found in the Rodentia generally. The tail varies greatly, being in some very small indeed, whilst in others it exceeds the length of the body; the sternum or breast-bone is narrow and long, and collar-bones are to be found in most of the genera; the pelvis is long and narrow. In most cases the hind limbs are longer and more powerful than the fore-limbs; in some, as in the jerboas (Dipus) and the Cape jumping hare (Pedetes caffer), attaining as disproportionate a length as in the kangaroos, their mode of progression being the same; the tibia and fibula are anchylosed; the forelimbs in the majority of this order are short, and are used as hands in holding the food to the mouth, the radius and ulna being distinct, and capable of rotatory motion. The feet have usually five toes, but in some the hind feet have only four, and even three. In point of intelligence, the rodents do not come up to other mammals, being as a rule timid and stupid; the brain is small and remarkably free from convolution. The cerebellum is distinctly separated from and not overlapped by the hemispheres of the cerebrum; the organs of smell, sight and hearing are usually well developed; the stomach is simple or in two sacs; the intestinal canal and cæcum long. The latter is wanting in one family.

Rodents have been divided in various ways by different authors. Jerdon separates his into four groups, viz. "Sciuridæ, squirrels;Muridæ, rats;Hystricidæ, porcupines; andLeporidæ, hares; which indeed are considered by some to embrace the whole of the order; to which has recently been added theSaccomyidæ, or pouched rats, whilst many systematists make separate families of the dormice,Myoxidæ; jerboas, Dipodidæ; voles,Arvidolidæ; mole-rats,AspalacidæandBathyergidæ; all included in the MURIDÆ; and theCaviadæ,Octodontidæ, andHydrochoeridæ, belonging to the HYSTRICIDÆ" ('Mammals of India,' p. 164).

However, the system that most commends itself is that of Mr. E. R. Alston, proposed in the 'Proceedings' of the Zoological Society, and founded on the original scheme of Professor Gervais, by which the order is subdivided into two on the character of the incisor teeth. Those which have never more than two incisors, coated only in front with enamel are termed SIMPLICIDENTATA, orSimple-toothed Rodents. The other sub-order, the genera of which have rudimentary incisors, as in the case of hares, rabbits, &c., and in which the enamel is spread more or less over all the surface, is termed DUPLICIDENTATAorDouble-toothed Rodents, and this is the system I propose to follow.

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