perisom. The plates of the disk are soldered together, so as to form a close mosaic (μvoeîov). The mouth-papillæ are fused into two lines, their number being only indicated by grooves. The lateral arm-plates are united together above and below, the upper and lower arm-plates are reduced to mere rudiments, and there are no tentacle pores beyond the first arm-joints.

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FIG. 34. -Dorynchus thomsoni, NORMAN. Once and a half the natural size; everywhere in deep water.

In our new species, which I name provisionally Ophiomusium lymani, the diameter of the disk is 28 mm., and the length of each arm 100 mm. in large specimens. The two lateral arm-plates, fused together above and below, form complete rings, their distal edge notched on each side for the insertion of seven arm spines, of which the lowest is much longer than the rest. The dorsal arm-plates are small and diamond-shaped, let in between the lateral armplates at the distal end of their upper line of

junction. The ventral arm-plates are entirely absent. This is a large handsome star-fish. I am not aware of any fossil form which can be referred to the same genus; but it looks like a thing which might be expected to have congeners in the upper chalk. Holothurids were not frequent, but the singular little Echinocucumis typica of Sars, covered with spiny plates, turned up in every sifting.

FIG. 35.—Amathia carpenteri, NORMAN. Once and a half the natural size. (No. 47.)

Crustacea are numerous; but we have here entirely lost the gigantic Arctic amphipods and isopods of the cold area.' A pretty little stalk-eyed form Dorynchus thomsoni, NORMAN (Fig. 34), small and delicate, and very distinct from all previously described species of the genus, is very widely diffused.

This crab, from its long spiny legs and light body, very often comes up entangled on the part of the rope which had been passing over the ground. Another handsome new species, Amathia carpenteri, NORMAN (Fig. 35), was common in the sandy chalkmud of the Holtenia ground.' The genus had previously been familiar as a Mediterranean form.

I quote from a preliminary notice of the Crustacea by the Rev. A. Merle Norman : "Ethusa granulata (sp. n.), the same species as that found off Valentia, but exhibiting a most extraordinary modification of structure. The examples taken at 110-370 fathoms in the more southern habitat have the carapace furnished in front with a spinose rostrum of considerable length. The animal is apparently blind, but has two remarkable spiny eye-stalks, with a smooth rounded termination where the eye itself is ordinarily situated. In the specimens however from the north, which live in 542 and 705 fathoms, the eye-stalks are no longer moveable. They have become firmly fixed in their sockets, and their character is quite changed. They are of much larger size, approach nearer to each other at their base, and instead of being rounded at their apices they terminate in a strong rostrate point. No longer used as eyes, they now assume the functions of a rostrum; while the true rostrum so conspicuous in the southern specimens has, marvellous to state, become absorbed. Had there been only a single example of this form procured, we should at once have concluded that we had found a monstrosity, but there is no room for such an hypothesis by which to escape from this most strange instance of modifi

cation of structure under altered conditions of life. Three specimens were procured on two different occasions, and they are in all respects similar.'

Mollusca are much more abundant and varied in the warm area than in the cold. Mr. Gwyn Jeffreys remarks, however, that there is not such a decided difference in the Molluscan fauna of the two regions as might have been expected from the difference in their conditions; very many species being common to both. At 500 fathoms the sponges are full of Pecten vitreus, CHEM., and Columbella haliæti, JeffreYS; and throughout the area species occur of many Molluscan genera, including Lima, Dacridium, Nucula, Leda, Montacuta, Axinus, Astarte, Tellina, Neæra, Dentalium, Cadulus, Siphonodentalium, Rissoa, Aclis, Odostomia, Aporrhais, Pleurotoma, Fusus, and Buccinum.

Taken as a whole the fauna of the warm area off the north of Scotland seems to be an extension of a fauna with which we are as yet very imperfectly acquainted, occupying what we must now call moderate depths, say from 300 to 800 fathoms, along coasts which are bathed by currents of equatorial water. The fauna of this zone is evidently extremely rich; and as it is beyond the reach of ordinary dredging from an open boat, and yet not at a sufficient depth to present any very great difficulty from a yacht of average size, its exploration seems to present just the combination of adventure and novelty to stimulate amateurs; so we may hope shortly to have its conditions and distribution cleared up. A most successful step in this direction has been made already by Mr. Marshall Hall, who,

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with his yacht Norna,' and with the aid of Mr. Saville Kent, has thrown a good deal of additional light upon the zoology of the warm area' off the coast of Portugal.

We left Stornoway on the 13th of September, and in the afternoon dredged for a few hours in Loch Torridon without much result. Late in the evening, steaming down Raasay Sound, we came upon the luminous forest of Pavonaria to which I have already referred. At noon, on the 14th, we were abreast of the Island of Mull, and on the 15th we were once more moored in the Abercorn Basin, Belfast, where we took leave of the Porcupine' and our highlyvalued friends her captain and officers; in the hope of meeting them again shortly, and thoroughly satisfied with the success of our summer's work.

On the 24th of March, 1870, a letter was read at the council meeting of the Royal Society from Dr. Carpenter, addressed to the President, suggesting that an exploration of the deep sea, such as was carried out during 1868 and 1869 in the regions to the north and west of the British Islands, should now be extended to the south of Europe and the Mediterranean, and that the council of the Royal Society should recommend such an undertaking to the favourable consideration of the Admiralty, with a view to obtain the assistance of Her Majesty's Government, as on the previous occasions. The official correspondence, with reference to the expedition of the summer of 1870, is given in Appendix A to the present chapter.

It was intended, as on the previous occasion, to divide this year's expedition into cruises; and again Mr. Gwyn Jeffreys undertook the scientific direction