70 A NATURALIST ON THE "CHALLENGER." 



hollow or chink. They are plucky birds, and the old ones 

 sometimes make dashes at the head of an intruder who goes 

 too near their nest. They had so little fear of man, from want 

 of experience of his cruelty, that we could have caught any 

 number of them with our hands. 



In vast abundance, all over the rocks, crawls about a crab 

 (Grapsus strigosus), the same as that already noticed at the 

 Cape Verde Islands. This crab has been referred to by nearly 

 all visitors to the rocks. It is far more wide-awake than the 

 birds, and keeps well out of reach, being thus of some difficulty 

 to catch. The crabs are all over the rocks, every crevice has 

 several in it. 



You are fishing, and you have put down at your feet a nice 

 bait, cut with some care and difficulty from a fish sacrificed for 

 the purpose. You are absorbed in the sport. A fish carries 

 off your bait ; you look down and see two crabs just disappearing 

 into an impracticable crevice, carrying your choice morsel 

 between them. You catch a fish and throw it down beside you. 

 Before long you find a swarm of crabs round it, tearing morsels 

 off the gills, using both claws alternately to carry them to their 

 mouths ; and a big old crab digging away at the skin of the fish, 

 and trying to bite through it. 



If a bird dies the crabs soon pick its bones, and I saw one 

 old crab profiting by our having driven off all the old birds, and 

 carrying off a young bird just hatched. The older crabs are 

 richly coloured, with bright red legs. The crabs have odd ways, 

 and curious habits of expressing anger, astonishment, suspicion, 

 and fear, by the attitude of their claws. When two old crabs 

 meet unsuspectingly in a crevice they dodge one another in an 

 amusing way, and drawing their legs together strut on tiptoe. 



In the tropics one becomes accustomed to watch the habits 

 of various species of crabs, which there live so commonly an 

 aerial life. The more I have seen of them the more I have been 

 astonished at their sagacity. I had, I do not know why, always 

 considered them as of low intelligence. 



Admiral Fitzroy gives an account of the large numbers of 

 fish caught off the rocks by his men, and states that they hauled 



