64 MAYOR— ROSE ATOLL, AMERICAN SAMOA. 



from the decomposed roots of the pisonia trees permeated this 

 coquina to a depth of several feet. All of the fossils found im- 

 bedded in the coquina are forms now living on the reef flat. Pro- 

 fessor C. B. Lipman found that the coquina in contact with the soil 

 contains 12.05 per cent, of phosphoric acid. 



On the wave-washed southeastern shore of Rose Islet some 

 modern beachrock has been formed and projects a few inches above 

 high tide level ; but this is more recent than the rocky matrix of the 

 islet, which is now elevated about 11 feet above high tide level. 



Sand Islet, which lies north of Rose Islet, is a mere accumula- 

 tion of fragments of lithothamnium, shells, and broken coral, and 

 is devoid of vegetation, and only about five feet above high tide 

 level. The sea must wash completely over it in time of storm. 



Several hundred boobies (Sula), most of which had half-grown 

 young, were nesting on the coral breccia of Rose Islet, while others 

 had constructed nests of sticks high among the branches of the 

 pisonia trees. A few boatswain birds with eggs were also nesting 

 in the trees, and several nearly grown young of the noddy (Anous) 

 were running over the ground, while adult noddies and sooty terns 

 visited the island at night. Frigate birds were hovering over the 

 island, but none were nesting. Wilkes states that the noddies and 

 sooty terns were nesting on Rose Islet on October 7, 1839, and these 

 species were still nesting when Governor Terhune visited the island 

 on January 10, 1920. 



A small brown-gray rat was abundant and specimens of it were 

 presented to the Bishop Museum in Honolulu, where they were 

 identified by Mr. J. F. G. Stokes as being a Malayan form which 

 appears to have become widely spread over Polynesia, being prob- 

 ably introduced by the early Polynesians themselves, who esteemed 

 them for food, and took much delight in hunting them for sport. 

 Apart from these very tame and abundant rats, the only other ani- 

 mals we observed were a small brown short-tailed lizard, identified 

 by Dr. Thomas Barbour as Lcpidodactylus lugubris, which is 

 abundant in Polynesia, and the larva of a sphynx moth {Celerio 

 Oken) feeding upon the portulaca. A few gnats and an occasional 

 house fly, which may have been introduced from the U. S. S. 



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