XV.-Description of a New Species of Cephalus, which it is proposed to name CEPHALUS COCHERANI, Cochrane's Sunfish.

By Dr T. S. TRAILL of Liverpool.

(Read 16th April 1825.)

CHAR. SPECIF. Cephalus corpore elongato, truncato subargenteo, spinis vel tuberculis carenti.

Sunfish with elongated but truncated, sub-argenteous body, destitute of spines or tubercles.

THIS small species is sufficiently characterized by its form, as a sunfish; and appears to differ from any described by systematic ichthyologists, so much as to entitle it to be reckoned a new species. It was found in the stomach of a Bonito or Albacore *, which was caught on the 17th of May 1822, in Lat. 18° S. Long. 81° W., by a sailor on board of the O'Higgins, Lord Cochrane's flag-ship. On this account I have proposed the name in honour of that gallant officer. A correct drawing, the exact size of the original, was made by a young Chileno then on board; and this having been presented to me by a gentleman, then acting as his Lordship's secretary, it accompanies the description of the fish. See Plate VI. Fig. 2.

• Either Scomber Pelamis or Scomber Thynnus.

a

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The drawing measures, from the snout to the extremity of the caudal fin, 11] inches. It is three inches in depth: the dorsal fin measures 2 inches in length; the anal not quite 2 inches; the pectoral 2 inches; and the caudal fin loths of an inch.

The general form of this species is more fish-like than that of any other of the genus. The separation of the dorsal, caudal, and anal fins is distinctly marked in the drawing, which seems to have been executed with much care. The habit of the body is said to be less compressed than the sunfish described by Pallas, so that “ a section of it presented a full oval, except towards the tail, where it was considerably thinner.” The skin of the body is described to me as having been covered with a sort of indistinct appearance of small scales, in size like those of a sole ; they were not imbricated, but adhered all round to the skin. The head, however, was quite smooth. The general colour of the fish was a dull silvery or plumbeous hue, which becanie nearly white, or of a cream colour on the belly. The eye was large and prominent *; the mouth a small circular hole with horny edges, but without any moveable lips. The top of the head was slightly flattened. A cartilaginous substance extended from the pectoral fin, so as to include the upper and fore part of the head, and returned by an acute anzlench from the snout toward the breast. The extent and form of this substance, which was, however, covered by the general integument, is well marked in the drawing

My informant had not observed the branchial apertures, from which we may conclude that they were small.

The general form of the pectoral, dorsal, and anal fins in the drawing is triangular and pointed. They as well as

. In the drawing it measures 0.6 inch in diameter.

the caudal are stated to have been placed on whitish carti. laginous substances, as there expressed, which were move. able by appropriate muscles. The upper part of the caudal fin projects beyond the lower ; and its general form ap

r proaches to the small segment of a circle, 4 or 5 inches in radius.

XVI.—Remarks on the Genus Scissurella of M. D'Orbigny, with a description of a recent British Species.

By JOHN FLEMING, D. D. F. R. S. E. &c.

(Read 19th May 1827.)

In the year 1809, I found, among a quantity of sand thrown up by the tide, on the Isle of Noss, Zetland, many of the rarer microscopical shells of the "Testacea Britannica." Among these, one appeared, remarkable for its Argonauta-like aspect. Upon sending specimens to my valued correspondent, the late George Montagu, Esq., I was not a little surprised to find, that he regarded it as nothing more than the fry of a Trochus! The shell being of a small size, I entertained some suspicion that it might be young, and not perfectly formed, and trusted to a future opportunity of obtaining larger specimens. In this, however, I was disappointed, as I never was able to detect the species at any subsequent period.

Three years ago, upon communicating specimens to that intelligent naturalist, Mr Dillwyn, he informed me that a genus for the reception of analogous species had been re

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