114 Charles Darwift. 



list of animals and plants being very restricted, but 

 when he turned to the ocean, here indeed was a 

 field in which months might be expended without 

 exhausting its treasures. Hardly a day passed but 

 the young naturalist went out on the great reef and 

 wandered among the coral groves, often combining 

 no little sport with the more aesthetic pleasures of 

 collecting. Thus one day, with Captain Fitz-Roy, 

 he was pulled up a lagoon, which abounded in 

 turtles. A man was stationed in the bow, and as 

 one was sighted asleep on the bottom, he dived 

 over, caught it by the neck, and was borne away at 

 a high rate of speed, much to the amusement of the 

 lookers on. Here, buried in the mud, was found the 

 giant clam, that is so powerful that natives have 

 been caught and held until the shell was dug out and 

 the animal killed. 



Keeling, as well as the other islands of the group, 

 was an atoll, a narrow reef, surrounding a shallow 

 lagoon, the former bearing cocoa-nut trees and other 

 plants, the seeds of which had washed ashore. To 

 show the divining mind of Darwin, a green stone 

 rock was found in the conglomerate of one of the 

 outer islands that was so entirely foreign to the sur- 

 roundings that it was evident that it must have 

 been brought there. Darwin assumed that it must 

 have come in the grasp of a tree root, and his theory 

 was shown to be plausible later, when he learned 

 from Chamisso, the naturalist, that the natives of the 

 Radack Archipelago obtained stones for various pur- 

 poses by hunting in the roots of trees that washed 

 ashore. 



