212 Cruise of the "Alert" 



while the soundings are so regular as to exclude the existence of 

 coral knolls. The general surface of the island is quite flat, and 

 has a mean elevation above the sea-level of about eight feet. 

 Immediately within the sandy beach above mentioned is a raised 

 inner beach composed of blown sand and lumps of coral, on which 

 flourishes a belt of low green Tonrnefortia bushes. After travers- 

 ing this, one walks over a rugged plain of honey-combed coral 

 rock, the interstices of which are in some places filled with sand 

 and vegetable mould, which supports a more or less general 

 mantle of scrubby grass, interspersed with several introduced 

 plants gone wild. Among these were cotton, sugarcane, papaws, 

 yams, gourds, cocoa-nuts, and perhaps a few others. It appeared 

 that none of these had been found to thrive, which no doubt 

 accounts for their present neglected state. We now ascertained 

 that the large tree which had attracted our attention from the 

 offing was a Casuarina, of which there were altogether two or 

 perhaps three on the island. 



There were no land birds. Sea birds, however, were very 

 abundant, and seemed in many ways to have partially adapted 

 themselves to the habits of their terrestrial congeners. The sand 

 and light soil, which in some places occupied the cavities in the 

 coral rock, were everywhere excavated by the burrows of petrels, so 

 that within an area of four square yards one might count as many 

 as a dozen. There were also smaller burrows not admitting 

 the hand in one of which I captured a land-crab. Walking 

 over the island small as it was proved to be very fatiguing 

 and aggravating, for after one had extracted a bruised ankle from 

 some treacherous hole in the coral, which the long grass con- 

 cealed, the next step, taken with misplaced confidence on an 

 inviting-looking patch of sand, would probably put the other foot 

 through the frail roof of a petrel burrow, into which it would 

 descend, to the alarm and indignation of its proper tenant, no less 

 than to the mortification of the explorer. 



Many gannets were breeding on the island. I approached 



