Among many interesting birds* procured in the above-mentioned manner, I may allude to Puffinus cinereus, a European species of shearwater, which was found to be generally distributed across the South Atlantic between the meridians of 28 degrees West and 1 1/2 degrees East; on two successive days, while in the neighbourhood of Tristan da Cunha, myriads of these birds passed the ship to the westward, apparently coming from that island. A few days afterwards, while 480 miles from the nearest land, we caught a beautiful tern (Sterna melanorhyncha) hitherto considered to be peculiar to Australia. (*Footnote. For the occurrence of Procellariadae during our outward voyage, with a view to determine the geographical distribution of the species met with by me, see Contributions to Ornithology by Sir W. Jardine, Bart. page 94.) PELAGIC ANIMALS. On several occasions the towing net* produced a rich harvest, especially one day when almost becalmed in latitude 34 degrees 40 minutes South and longitude 4 degrees West. The surface of the water was absolutely teeming with marine animals. Of these a small Physalia and a Velella (V. emarginata ?) were the most plentiful. The latter curious animal, consists of a flat oval expansion, an inch and a half in length, furnished below with numerous cirrhi and a proboscidiform mouth, and above with an obliquely vertical crest, the whole of a rich blue colour with white lines and dots, the soft parts conceal a transparent cartilaginous framework. The crest acts as a tiny sail (hence the name) and communicates to the animal a slow rotatory movement while drifting before the wind. Two kinds of Janthinae (J. globosa and J. exigua) molluscs with a fragile, snail-like shell, and a vesicular float, were drifting about, and, together with a very active, silvery-blue Idotea, half an inch long, prayed upon the Velellae. At another time, among many other pelagic crustacea, we obtained three kinds of Erichthus, a genus remarkable for the glassy transparency of its species, also Hyalaea inflexa and H. tridentata, curious pteropodous molluscs which swim near the surface. (*Footnote. Not having seen a description of this useful instrument, I may mention that the kind used by Mr. Huxley and myself, consisted of a bag of bunting (used for flags) two feet deep, the mouth of which is sewn round a wooden hoop fourteen inches in diameter; three pieces of cord, a foot and a half long, are secured to the hoop at equal intervals and have their ends tied together. When in use the net is towed astern, clear of the ship's wake, by a stout cord secured to one of the quarter-boats or held in the hand. The scope of line required is regulated by the speed of the vessel at the time, and the amount of strain caused by the partially submerged net.) ARRIVE AT SIMON'S BAY.