Volume I Part 8 (1/2)

Caught a slug-like animal (Holothuria) this evening, or rather more closely resembling a caterpillar.

Length from head to root of tail 0.7 inches.

Length of tail (or rather gelatinous protuberance) 0.25 inches.

Breadth (broadest part at root of tail) 0.22 inches.

Narrowest part (near head) 0.15 inches.

Length of head 0.12 inches.

Head of light red colour, mouth apparent, motion of head like a caterpillar's when touched, shape cylindrical, body gelatinous, intestines apparent and full.

November 16. Longitude 102 degrees 40 minutes east; lat.i.tude 28 degrees 5 to 6 minutes south.

Since we have pa.s.sed the 95th parallel of longitude, and 32nd of lat.i.tude up to the present moment we have been out of the region of birds, for during the whole of this period I have seen but two, one of which, a Petrel, has this moment visited us. We have however seen more Sea-jellies, Acalepha and Mollusca than before, and those of a much more beautiful kind. Thus nature has made up for the deficiency of one tribe of animals by the profuseness with which she has distributed another.

November 18. Lat.i.tude 26 degrees 57 minutes south; longitude 105 degrees 22 minutes east.

We caught a crustaceous animal (Phyllosoma, see Ill.u.s.tration 11) which was perfectly transparent; it was furnished with twelve legs on what I considered the hinder part of its body, and four antennae in front, which have their tips of a bright pink colour, and two eye peduncles by their side, which terminate in little bags containing some blue matter (their eyes). It was furnished also with two legs underneath. These are just shown in the figure near the centre of the body, and between those underneath the insect there was a slight projection, with two little lumps on each side. In this projecting part there appeared to be an opening. When it was taken out of the water it stood upright on its legs and crawled a little like a large beetle, but soon died. In the water it swam with the legs, and the last joint appeared to be feathered. It will be seen that there is a great irregularity in the position of the legs of this insect. The specimen appeared to me to be in some respects imperfect; but I figured it exactly as it was, without blindly guessing at its perfect state. It was not thicker than the thinnest wafer. The back was marked with curved lines, exactly in the manner I have represented. It shrank instantly when touched. The two last joints of the long legs were furnished with thorn-like spikes.

Length of tail 0.37 inches.

of the body 0.2 inches.

of the thorax and head 0.3 inches.

of the entire animal 1.4 inches.

Breadth of body 0.62 inches.

Ditto of thorax 0.51 inches.

Length of third leg 1.9 inches.

Length of second leg 1.7 inches.

Length of hindermost leg 0.6 inches.

Length of eyes, peduncles 0.4 inches.

We caught a second animal of exactly the same size as the one figured, but apparently much more perfect. Each of its tentacula terminates in a small feathering tip when it is in the water, like the little figures at the side, and by the help of which they swim; these have a h.o.r.n.y feel to the touch, are dest.i.tute of smell, and look like a transparent scale when they lie in your hand.

We also caught this day some little transparent sh.e.l.ls (Cuvieria) of a cylindrical form, and blunt at the end; they put out two little fins with which they swam.

I was unfortunately too unwell this day to describe all the other specimens we caught, which were numerous. The sea was full of small acalepha, and in the midst of a shoal of these a whale was seen.

November 19. Lat.i.tude 25 degrees 50 minutes south; longitude 106 degrees 22 minutes east.

Birds first re-appeared again. I saw a large flock of two kinds, but was not near enough to ascertain what they were. I have before noted the fact that almost at the exact point where the southern birds of the family Longipennes disappeared those sea-jellies (acalepha) which have the power of stinging, began to show themselves; previously to our pa.s.sing this point I had not seen one: I saw several however today at no great distance from this flock of birds.

We saw float by this afternoon one of the acalepha, apparently about two feet long and shaped generally like a water snake; its tail had fins like that of an eel, of a purplish tinge; I could distinctly see its head and various vessels in its interior for it was quite transparent. We had no net ready but threw a stick with a piece of string attached to it, the string pa.s.sed under it but in pulling up cut through it as though it had been jelly.

Caught an animal (Cymothoa) shaped exactly like a woodlouse:

Length 0.4 inches.

Length of antennae 0.15 inches.

Breadth of body 0.12 inches.

It had six legs, and a tail-like fin behind on each side, and nine rings on its back so that it could roll itself almost into a ball, these rings extended no farther than from its head to within 0.12 inches of its hinder extremity; colour very pale blue down the back, bright prussian blue on each side; it crawled about when taken out of the water, and lived for some time; its fins, or fin-like legs, when it thus crawled about, were folded under its tail; eyes distinct.

MOLLUSCA.