or one might rather say glowing, up to the centre; then that would fade, and a defined patch, a centimetre or so long, break out in the middle of an arm and travel slowly out to the point, or the whole five rays would light up at the ends and spread the fire inwards. Very young Ophiacanthæ, only lately rid of their 'plutei,' shone very brightly. It is difficult to doubt that in a sea swarming with predaceous crustaceans, such as active species of Dorynchus and Munida with great bright eyes, phosphorescence must be a fatal gift. We had another gorgeous display of luminosity during this cruise. Coming down the Sound of Skye from Loch Torridon, on our return, we dredged in about 100 fathoms, and the dredge came up tangled with the long pink stems of the singular sea-pen Pavonaria quadrangularis. Every one of these was embraced and strangled by the twining arms of Asteronyx lovéni, and the round soft bodies of the star-fishes hung from them like plump ripe fruit. The Pavonariæ were resplendent with a pale lilac phosphorescence like the flame of cyanogen gas; not scintillating like the green light of Ophiacantha, but almost constant, sometimes flashing out at one point more brightly and then dying gradually into comparative dimness, but always sufficiently bright to make every portion of a stem caught in the tangles or sticking to the ropes distinctly visible. From the number of specimens of Pavonaria brought up at one haul we had evidently passed over a forest of them. The stems were a metre long, fringed with hundreds of polyps.

Ophiocten sericeum, FORBES, and Ophioscolex purpurea, D. and K., were likewise very common, and

The

in sand patches, Ophioglypha sarsii, LÜTKEN. most abundant asterid was Asteropecten tenuispinus, always a marked object from its bright red colour with here and there an example of Archaster andromeda and Pteraster militaris. Every haul brought up several specimens of the so-called large

FIG. 25.-Archaster verillifer, WYVILLE THOMSON. One-third the natural size. (No. 76.)

form of Echinus norvegicus, here of a pale colour, somewhat conical, and looking suspiciously like small forms of E. flemingii.

Along with one or two specimens of Archaster andromeda, we took at Station 76 an exceedingly beautiful Archaster (Fig. 25), certainly by far the finest species yet dredged in the Northern Seas.

The arms are flattened, somewhat square in section

owing to the position and size of the marginal plates, which run up nearly vertically from the side of the unusually wide ambulacral groove till they meet the edge of the perisom of the dorsal surface. The marginal plates are thickly covered with rounded scales and bear three rows of spines-one at the upper edge (and this series in combination form a fringe round the dorsal surface of the star-fish), one near the centre, and one a little farther down towards the ventral edge. The ambulacral groove is bordered by obliquely placed combs of spines, short towards the apex and centre of the arm, but becoming longer towards its base, and forming at the re-entering angles between the ambulacral grooves large singularly beautiful pads; each plate bearing a double row of spines, and each spine having a second short spine or scale on the end, an arrangement which adds greatly to the richness of the bordering. The inner spine of each comb on the side of the ambulacral groove is longer than the others, and bears on the end a little oblong calcareous plate usually hanging from it somewhat obliquely like a flag, with sometimes a rudiment of a second attached to it in a gelatinous sheath, which makes it probable that it is an abortive pedicellaria. From this character, which is one which cannot escape observation, I have called the species vexillifer.' I know no star-fish in which the ambulacral grooves are so wide and the ambulacral tubes so large in proportion to the size of the animal as in this species. The dorsal perisom is closely covered with rosette-like paxillæ. The colour is a pale rose, with a tinge of buff. The ambulacral tubes, which when the animal

is living present a very marked feature from their great size, are semi-transparent and of a pale pink colour.

We now took a run once more to the southward, recrossing the boundary of the cold stream, and sounding successively in 290 fathoms, with a bottom temperature of 5°3 C., and in 76 fathoms, with a temperature of 9°4, practically the same result as in the former case; and in the next four Stations, 80, 81, 82, and 83, we repeated the operation inversely, sounding in 92 fathoms, with a temperature of 9°7 C.; in 142, with 9°·5; in 312, with 5°2; and in 362, with 3°0.

After a run of about sixty miles in a south-easterly direction nearly parallel with the 100-fathom line, on the morning of Saturday the 4th of September we sounded in lat. 59° 34' N., long. 6° 34′ W., with a depth of 155 fathoms and a temperature of 9°5 C. Two other Stations after running distances of six and eight miles only took us once more over the edge of the bank and into the cold river, the first giving a depth of 190 fathoms, with a temperature of 9°.3, and the second 445 fathoms, and - 1°0.

As we were satisfied for the present with our work in the cold area, and as the next day was the day of rest, we steamed quietly westwards for about 100 miles, past the Butt of the Lews and beyond the entrance of the channel to Station 87, lat. 59°35′ N., long. 2° 11′ W., a point nearly in the middle line of the deep water of the channel, and consequently in the axis of the cold stream, the line in which the peculiarities of the cold area are most pronounced. Here a sounding gave us a depth of 767 fathoms and

a bottom temperature of 5° 2 C. We were thus in the warm area, and the dead-cold water of the cold area lying fifty or sixty miles off, with the bottom at a higher level, was completely banked in. The bottom temperature here corresponded so closely with that of the same depth in the Rockall Channel that apparently scarcely a drop of the Arctic in

FIG. 26.—Zoroaster fulgens, WYVILLE THOMSON. One-third the natural size. (No. 78.)

draught makes its escape in this direction. The dredge here brought up half a ton of Atlantic globigerina ooze,' a load which tested its tackle and the donkey-engine to the utmost. The weight of the dredge itself with the weight attached was 8 cwt., so that altogether the burden reached not