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.

On March 8th, we anchored in Simon’s Bay; our passage from Rio de Janeiro, contrary to expectation, had thus occupied upwards of five weeks, owing to the prevalence of light easterly winds (from north-east to south-east) instead of the westerly breezes to be looked for to the southward of latitude 35 degrees South.  We were fortunate, however, in having fine weather during the greater part of that time.

The period of our stay at the Cape of Good Hope was devoted to the construction of a chart of Simon’s Bay and its neighbourhood, which has since been incorporated with the previous survey of Captain Sir Edward Belcher in H.M.S.  Samarang, and published without acknowledgment.  The requisite shore observations were made by Captain Stanley and Mr. Obree, while Lieutenants Dayman and Simpson conducted the sounding.  Our detention was lengthened by a succession of south-east gales, and the state of the weather throughout was such that during the period of twenty-one days the sounding boats were able to work on six only—­the other fine days were devoted to swinging the ships for magnetical purposes.  It was also intended to survey the Whittle shoal in False Bay, but when we sailed, the weather was so thick and unsettled, that Captain Stanley was reluctantly obliged to give it up.