As might be expected, I found regular basaltic crystals in this valley, and also a variety of quartz ore, and other crystals, in the veins traversing the basalt. I also found the following remarkable section:
This was in a side valley or ravine leading from Gregory’s Valley in a southerly direction.
On going down to the sea I found many species of starfish. I brought away three species of these with me. Two Species Pentagonal; one species Quadrilateral.
First species Pentagonal length of side 0.55 inch.
Second species Pentagonal length of side 0.50 inch.
Quadrilateral length of side 0.55 inch.
I found a sort of worm in the coral which had the power of extending its head like an English worm; its body then appeared to be composed of two portions, the fore part being much slighter than the other. Its dimensions were:
Length of fore part of body 0.4 inch.
Length of hind part 0.6 inch.
Breadth, or diameter of cylinder 0.1 inch.
In the coral there was also another insect, not unlike a centipede.
Length 0.9 inch.
Breadth at head 0.08 inch.
In the inmost recesses of the coral there was a minute bivalve shell and also a very minute species of crab.
One remarkable circumstance relating to St. Helena is that it is of a basaltic formation exactly resembling that of the Isle of France and the North-west of New Holland; and that, although so widely separated in longitude, these places lie in nearly the same latitude.
When you quit the sandstone ranges of the North-west of Australia reptiles which have been before very numerous at once become scarce. I never saw a snake in this great basaltic district although there were plenty in the sandstone. This however is only negative evidence. Brookes, in his History of St. Helena (second edition page 24) says: “There are neither frogs, toads, nor snakes in the island.” In the Isle of Bourbon there are neither toads nor snakes. In the Mauritius likewise there are neither toads nor snakes, and only one species of frog, whilst the bones of the land tortoise (Testudo indica) are only found in a fossil state. Also, the highest land in St. Helena is 2800 feet; in the Mauritius about 2900 feet (scarcely); and in the volcanic district of North-west Australia about the same height.
July 26. At sea.
We caught a great variety of shrimp-like animals; these little things when disturbed emitted a brilliant phosphorescent light. We saw scarcely any gelatinous animals.
July 29.
Caught two small crabs (Nautilograpsus); these species have the power of swimming by means of the fringe-like fins with which their legs are provided. Several other crabs were also caught; some with their eggs attached, and two varieties of shrimp-like animals with eggs. Where these were abundant the sea was very luminous. Four or five of these were of a brilliant prussian blue colour, with silver-coloured spots on the back; others were of a very delicate pink colour; the tentaculae of both of them were of a delicate prussian blue colour.