htception of his Famous Theory. 27 



In this island robber the observer must have found 

 a suggestion for his famous theory of the struggle 

 for existence and the survival of the fittest. The 

 author has watched a similar scene in the Gulf of 

 Mexico, where the Grapsus would attack even the 

 birds. Sir W. Symonds states that he has witnessed 

 the same at St. Paul's, the crab dragging young birds 

 away to devour them. 



Darwin found little of interest here from a botani- 

 cal standpoint, not even a single plant or lichen 

 appearing, though several spiders, flies, moths, and 

 beetles made the barren rock their home. If St. 

 Paul's was deficient in vegetation, it abounded in 

 marine forms of interest, the vast area of submerged 

 rock, with its sea-weed masses, affording ample 

 ground for fishes of infinite variety, while sharks were 

 so plentiful that it was a constant struggle between 

 them and the men. The moment an edible fish was 

 hooked a watchful shark rushed at it, carrying it 

 away before it could be taken in, this occurring so 

 frequently that one man was required to fight these 



.pirates of the sea while another hauled in the fish. 

 These days were marked by indefatigable energy 



|on the part of the young naturalist. When not in- 

 vestigating or peering among the rocks with hammer 



tor collecting-glass in hand, he was at work in his 

 cabin studying the strange animals he had found, 

 and making notes in his log, as to the colour, habits, 



|and the thousand and one points of interest to the 

 lover of science. 



From St. Paul's the Beagle bore away for Fernando 

 le Noronha, a desolate ancient volcanic rock upon 



