to which of these the few specimens recorded as killed in Great Britain belong. These gulls are very closely allied, and yet require careful comparison. The one is Pagophila eburnea (Phipps), (Voyage to North Pole, 1773); the other Pagophila brachytarsus (Halböll), (in Bruck's Paper, Cab. Journ. fur Ornith., 1855, p. 287). The latter is distinguished by its smaller size, greater comparative length of wing, short tarsi, and darker bill, tipped with bronze. My principal reason for alluding to these is, that a beautiful specimen of the latter form was shot a few years since in Caithness by Mr Shearer, and is now in my possession (vide Proceedings of Royal Physical Society, vol. i. p. 4). At the time I considered it as the old P. eburnea, but I find it now belonging to the long-winged form, and as such the first recorded in this country.

The thanks of the Society were voted to Sir William Jardine for his valuable communication.

III. Notices of the Hen Pheasant assuming Male Plumage, with an Exhibition of the Diseased Ovaries. (Various Specimens were exhibited.) By JOHN ALEX. SMITH, M.D.

The bird, with the preparation of its diseased ovaries, which I shall first notice, were brought for exhibition from the Anatomical Museum of the University. It was presented to the Museum by Captain J. W. P. Orde of Kilmory, Argyllshire, in which neighbourhood it was shot, and displayed the characters of the male, especially in the plumage of the head and neck. The injected preparation of the carefully dissected ovaries showed the atrophied state considered to be the common accompaniment of this assumption of the male plumage, but which is also said to be dependent on age. Mr Small, bird-stuffer, George Street, sent for exhibition another of these well-known varieties. In this instance the male plumage was more brilliant than in the last, and the ovaries which were exhibited showed a similar state of atrophy. This bird was the property of W. H. May, Esq., Wellwoodhouse, Muirkirk, Ayrshire. Mr Sanderson, bird-stuffer, George Street, had, at my request, sent another specimen of the hen pheasant assuming male plumage (now exhibited), which, in addition to the plumage, showed also the red warty cheeks of the male,

but the legs were slender, and, as in all the other instances, wanted the spurs of the male. This bird, however, had the peculiarity of its ovaries being perfectly healthy, showing as they did numerous ova; the mass developed were as large as barley, and a few nearly the size of peas. The other viscera appeared healthy. The bird belonged to the Bohemian or light-coloured variety of the pheasant. It would be of some interest, for the sake of comparison, that the period of the year should be stated when birds of this kind are examined; this one, from Peeblesshire (owing to the peculiarity of its plumage), was shot in the beginning of April. A very fine specimen of the true Phasianus torquatus, Tem., was also exhibited; it is the Chinese original, with the Phasianus colchicus, of our common ring-necked varieties, and is seldom seen in so pure. and distinctive a state of plumage. The bird was the property of Mr W. H. May, Muirkirk, in which neighbourhood I believe it was killed.

Captain Orde stated he had examined other specimens of these so-called mule-birds; in one he found the ovaries enlarged by a tumour or abscess,-another diseased state.

IV. Observations on British Zoophytes. (1.) Coryne implexa (Alder). (2.) Coryne (margarica, mihi) implexa (Alder). (3.) Bimeria vestita (4.) Garveia nutans. By T. STRETHILL WRIGHT, M.D., &c.

Descriptions of Plates.

PLATE III.

Fig. 4. Bimeria vestita; a, single tentacle, the clothed portion studded with parasitic Algæ:

5. Eudendrium arbuscula, stalked cluster of double spermatic sacs.

6. Section of double spermatic sac-a, tubercle containing, c, barbed

thread-cells.

7. Psuchastes glacialis.

1. Coryne implexa (Alder).

Under the title of Tubularia implexa, my friend Mr Alder has described a zoophyte discovered by Mr R. Howse in 40

fathoms water, 30 miles from Holy Island. Mr Alder's description of it is as follows:-" Tubularia implexa.-Tubes small, very slender, generally more or less contorted below, smooth, wrinkled or regularly annulated beneath a smooth transparent epidermis; slightly and subunilaterally branched; the branches going off nearly at right angles to the stem, and a little constricted at their base; gregarious, forming a denselytangled mass of half to three-quarters of an inch in height.

The polyp of this zoophyte had not been observed, for which reason Mr Alder considered that its claim to a place in the genus Tubularia could not be fixed very decidedly. Its most remarkable feature is the structure of the corallum or polypidom, which is divided into two coats, as in Plate III., fig. 6; a structure hitherto observed only in one other species, the Campanularia caliculata of Hincks. Mr Alder kindly sent me a specimen of his Tubularia implexa, which, after a careful examination I concluded to be, not a Tubularia, but a Coryne; and I wrote to Mr Alder to that effect. Fortunately, although the specimen was destitute of polyps, portions of the polypary or cœnosarc still remained, and I found in its tissues two kinds of thread-cells, the one oval, and containing a barbed dart (fig. 7, a), the other cylindrical, with almost truncated extremities, in which the thread was not conspicuous. (b), The first of these resembled very closely the oval, barbed thread-cells of Coryne decipiens; while the second, although much larger, evidently corresponded to the long, slender thread-cells found on the body within the corallum, and especially in the tips of the growing shoots of the last named zoophyte.

The internal layer of the corallum is brown and of horny texture; the external coat colourless and membranous. The first is frequently annulated; the second not so, but is occasionally gathered in longitudinal folds. I am disposed to think that this coat is the "colletoderm," or glutinous covering of the corallum (in this species highly developed and indurated), separated from the inner coat by the action of the spirit in which the specimen was immersed. In all the Corynes I have examined, this "colletoderm " forms a thick layer over the corallum, especially in the neighbourhood of the polyp.