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the hooked spine, and other characters, as those from Scotland. Dr Dickie added to his kindness by forwarding part of an arm, marked Ophiocoma minuta, by the late Mr Thompson, and which formed part of that lamented gentleman's collection, and on this I find similar hooked spines of both sorts; and if this (0. minuta is a good species, I have several specimens from Peterhead and Wick, and thus have another addition to our list. Should Ophiocoma rosula be found without these jaw-like spines, the one now described will be, if nothing else, a new species. The following reasons have induced me to lay these imperfect observations before you-First, to ask those who have time and opportunity, and are placed in good localities, to work out the history of these spinigrade animals; for we want, in addition to the beautiful figures given by the lamented Forbes, each species figured with dissected sections of spines, body, and ray plates, &c. These new characters may lead to other discoveries, and a standard be arrived at by which genera and species may be satisfactorily made out much better than at present. Second, When I had the pleasure of accompanying Sir Roderick Murchison, the past summer, on his geological tour, he told me that some one had figured and described certain minute fossils found in Silurian rocks as jaws of animals, and which he (Sir Roderick) thought were portions of starfishes. I sketched one of the jaw-like forms I had met with in Ophiocoma rosula-this, he thought, resembled in some measure the supposed jaws taken from the Silurian rocks. Should this be the case, by giving publicity to this discovery I hope to do good both to Zoology and Geology.

VI. Notice of the UKPAM, a large species (probably new) of Sting Ray (Trygon, Cuv.), found in the Old Calabar River, Africa. (Two young specimens were exhibited.) By JOHN ALEXANDER SMITH, M.D.

The Ukpam is the native African name of a species of Ray which is found in the rivers of Old Calabar, on the west coast of tropical Africa. This fish appears to grow to a great size, and specimens have been taken which measured 4 feet across, and about the same length from the snout to the insertion of the tail, and 10 feet in length to the point of the tail. A full-grown individual is described as being quite a heavy enough load for four men to carry from the river side. It occurs in considerable abundance in the Old Calabar River, and is much sought after by the natives, who consider its flesh as a great delicacy, and capture the fish by striking it through with a barbed spear, while lying partially concealed in the sand or mud in the bed of the river. It has been taken near the bar, at the mouth of the river, where the water of course is salt, and also up the river as high as Uwet and

Umon, which are about 150 miles from the bar, and where, although the river still rises and falls with the tide, from there being always a strong downward current, the water is perfectly fresh, and never even brackish. The two young specimens now on the table were sent home some time since by Mr Archibald Hewan, surgeon to the Old Calabar Mission of the United Presbyterian Church, to the members of which mission the Society has been again and again indebted for various interesting additions to the knowledge of the zoology of Western Africa. The natives have a curious theory that these young fish, somewhat after the manner of the young of the marsupial animals, take shelter in the maternal organs, which they leave or enter at pleasure, until they are old enough and strong enough to take care of their personal safety. Mr Hewan, however, says that one of the natives, who prides himself on his skill in capturing this rather formidable creature, denies this statement altogether; so that, probably the pain of being struck through with a spear at its capture, causing in some instances the expulsion of the nearly mature young, may have given rise to this idea (should it turn out to be false); which, however, is generally believed among the natives. Mr Hewan has promised to give some attention to the subject, so that we may hope to be favoured with more information before long.

The specimens exhibited, Mr Hewan says, are very young. He was asked to go down to the river side, where a native had in his canoe a large male and female Ukpam he had just captured. These fishes measured about 4 feet across; and while Mr Hewan was standing near the canoe, "the native was searching the body of the female, because he did not see the young ones (the specimens now exhibited) in the canoe where he had left them. He had not searched the canoe thoroughly, and so, not finding them in the oviduct, he repeated his search in the canoe, and there they were lying. His searching the body was strong presumptive evidence that he had found them there before; but that they returned there seems only a theory, unless the native's word be taken." Mr Hewan states these fish were alive and active when he got them; and, as far as we can judge by their appearance, they

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must both have been but recently ushered into the world. If the native theory is correct, the Ukpam would appear therefore to be viviparous, its young being hatched in the oviduct prior to expulsion-and to have two young ones, or, at least, the birth of one young one must very rapidly succeed the other; as I am unable to detect any difference of age, except in the rather greater size and bulk of one of the specimens, which, however, appear to resemble one another very closely in all respects.

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These young specimens of the Ukpam are of a uniformly rounded outline, rather longer than broad, and diminish a little in breadth, towards the long whip-like tail; one measures from the slightly projecting snout to the extremity of the tail 40 inches; the other is about one inch shorter; the body of the larger one measures 11 inches to the extremity of the inner lobe of the ventral fins. The tail itself is 30 inches in length. The fish is about 103 inches in its greatest breadth a little in front of the middle, the smaller one measuring about 10 inches; the pectoral fins surround the head, and are produced in front in the mesial line about of an inch from this point, to the large and very prominent eyes, it measures 2 inches; and the eyes are 2 inches apart. The upper eyelid has a rounded adnate projection There is a large round-shaped fossa on each side, immediately behind and below the eyes, of an inch in length by about an inch in breadth, across the back part of which are the large temporal openings or blow-holes. The body above is full and thick, rising up from the disc at about 2 inches from the snout, and forming an oval rounded projection slightly contracted in the middle, which is surrounded by the flattened and thin margins of the pectoral fins; this raised and projecting part of the body measures about 8 inches long, by 5 across the abdomen. The pectoral fins are rounded along the margins of the fish, and posteriorly they are deeply rounded at their termination about

an inch from the insertion of the tail; and, with the ventrals, complete the general broadly ovate character of the fish. The ventrals are undivided posteriorly; a thickish rounded lobe forms the inner margin of the fin, and projects beyond it of an inch; these lobes are present in both of the specimens,

and form, probably, the claspers of the male fish; the two fins are connected together by a frenum behind the anal openings. The rounded posterior edge of the ventral fin measures about 2 inches across, and the root of the fin 1 inch across.

There is a general rough, granular appearance over the upper surface of the body, which is now of a muddy yellowish brown colour, and this granular appearance diminishes towards the sides as you approach the pectoral fins, which are smooth above. The granules are larger and more distinct, and become circular in shape, as you approach the mesial line of the fish, which from the posterior half of the body gives indications of larger circular plates or shields, these become still larger as you approach the base of the tail, and cease in the mesial line a little beyond it, within an inch or so from the insertion of the spine. Beyond this, again, a smaller double range of ovalshaped obliquely-placed bony scales or granules can be traced for a considerable distance along the sides of the slender tail; an indication, apparently, that as the fish increases in size with age, there will be a greatly increased development of these bony spines and shields on the back and tail. About 33 inches from the insertion of the tail you find a firm bony moveable spine inserted into the middle line of its upper surface, corresponding to the barbed spine of the sting Rays; it is about an inch in length, and is ths of an inch in breadth, but has no barbs on its sides, being smooth and edged with membrane, and terminates in a rounded and flattened button-like extremity, rather more than of an inch in length. The sword in this instance is covered by a scabbard; what change age may make on it I am of course unable at present to say. Mr Hewan has promised to send the tails and jaws of adult individuals of both sexes for examination; so that I hope to be able at another opportunity to enter more fully into a description of its adult characters.

The under surface of the fish is lighter in colour and smooth; the slightly arched mouth is about 2 inches from the extremity of the snout, and measures ths of an inch in width; its jaws are covered with alternate rows of small rounded or oval-shaped teeth with transverse markings, closely set together. Behind the teeth of the upper jaw there is a deep fringed velum, and a shallower smooth-edged velum lies

behind the teeth of the lower jaw, five small warty-like papillæ projecting behind it into the mouth. In front of the mouth. you have the free transverse slightly-fringed margin of the undivided nasal membrane, with its frenum in the mesian line, attaching it to the upper jaw; it is also free at its outer margins (leaving an obliquely placed nasal opening on each side), and thus forms altogether a double flap, which covers the large transversely placed nasal organs. About 14 inch behind the mouth, the double row of spiracles or gill openings, five in number on each side, run backwards in a curved direction; and about an inch behind them, but in the mesial line, at the forepart of the abdomen, you find a small projecting body which measures ths of an inch in length by 4th of an inch in breadth; it is 3ths inches distant from the mouth, and from it to the anal opening measures 4 inches; it appears to be the last remains of the now all but absorbed vitellus or yolk of the egg, the umbilical bag which nourished the fish in its younger stage of existence. The whole length of the fish along its under surface is, from the snout to the middle of the anal opening, 10 inches, and from the anal opening to the extremity of its slender and pointed tail 30 inches.

The tail is rounded above; it measures about an inch in breadth at its insertion to the body, and tapers to a minute point. Nearly opposite the insertion of the spine above, there begins on the under surface a narrow fin without rays, which projects about one-tenth of an inch, and runs with a low and free margin for about 3 inches down the grooved under-surface of the tail.

As this fish advances in age, its body and tail are described as becoming very rough and spiny above, and, in some instances, the tail is said to become comparatively short, at least in the old male. The fish is described as using its tail as a weapon of defence, striking its enemies with this formidable weapon, and inflicting severe and even dangerous wounds. It is stated to feed on small eels, which are abundant in the mud of the river's bed.

It is with much diffidence I have ventured to lay before the Society a notice of this African fish. It belongs to the SUBFAMILY of the Trygonina; and if the peculiarity of the spine or spur on the tail is a character of any importance,

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