A NATURALIST IN BRAZIL. 13 
swarm of little, gaily-painted, gilded and silvered fishes, and 
a crystal jelly-fish ; a host of little shells, half of them ten- 
anted by hermit-crabs, and swarms of little crustaceans. 
Now we will wreathe in among the sea-weeds, here and 
there, the necklace-like, pearly body of a marine worm, and 
we shall then have an aquarium, wonderfully like those 
which nature has so liberally strewn over the surface of the 
Brazilian coral-reefs. 
Under the dead corals one finds great numbers of a large 
Ophiura, with a small disk-shaped body, and long snaky 
arms (O. cinerea Lyman), and by dint of a little patient 
examination, with the aid of a pocket lens, he may collect 
hundreds of species of animals from one of these pools alone. 
At the Abrolhos Islands, I found a few specimens of a large, 
almost pentagonal starfish, which is very common in the 
West Indies ( Oreaster gigas Lütken). This also occurs at 
Bahia, together with a very well-known West Indian shell, 
quite common as a mantel-piece ornament, and which has 
the misnomer of Cassis Madagascarensis ! 
The corals, which go to make up the Santa Barbara reef, 
are principally Acanthastrea, Heliastrea, Siderastrea, Fa- 
via, Porites, Millepora. The reef-rock, like that of the 
reefs, is a compact, hard, white limestone, which appears 
to show scarcely any organic structure. The corals are so 
broken and cemented together, that their structure is quite 
obliterated. The Santa Barbara reef, then, forms a wharf- 
like structure, partially surrounding the island. It has 
grown upward as far as possible, i.e. to a level a little 
above that of low tide, when the corals having died, further 
growth is stopped. It varies much in width, but in some 
places it reaches even 400 feet. At the south-west extrem- 
ity of the island there is a little islet, composed of a pile of 
boulder-like masses of trap, and known as the “Cemetery,” 
which at low tide is united to the main-land by this reef. A 
reef of the same kind is formed around part of the neighbor- 
ing island of Redonda, and Siriba also has one. 
