AGASSIZ : LETTERS TO THE HON. GEORGE M. BOWERS. 73 



The two lines centring at Easter Island developed the "Albatross" 

 plateau indicated on the " Challenger " bathymetrical charts, ou the 

 strength of a few soundings reaching from Callao in a northwesterly 

 direction, and of a couple of soundings on the 20th degree of latitude. 

 The Albatross plateau is marked as a broad ridge separating the 

 Buchan Basin from the deep basin to the westward, of which Grey- 

 Deep and the Moser Basin are the most noted areas. 



Our line from Easter Island to the Galapagos showed a wonderfully 

 level ridge, varying in depth only from 2020 to 2265 fathoms in a dis- 

 tance of nearly 2000 miles. The soundings we made to the eastward 

 from the Galapagos to the South American coast, and to the westward 

 of Callao, as well as on the line from Callao to Easter Island, all indi- 

 cate a gradual deepening to the eastward to form what the " Chal- 

 lenger " has called the Buchan Basin with a greatest depth of 2400 to 

 over 2700 fathoms, and passing at several points near the coast to Milne, 

 Edwards, Kriimmell, Richards and Haeckel Deeps, some of them with a 

 depth of over 4000 fathoms. According to the " Challenger " sound- 

 ings, the Juan Fernandez plateau connects with the Albatross plateau, 

 and forms the southern limit separating Buchan Basin from the Barker 

 Basin to the south of the Juan Fernandez plateau. 



At Easter Island we found our collier awaiting our arrival. We 

 moved from Cook Bay to La Perouse Bay to coal, as there was less 

 swell there than in Cook Bay, where we could scarcely have gone 

 alongside to take in coal. 



Considerable shore collecting was done at Easter Island. We must 

 have brought together at least 30 species of plants. The flora of Easter 

 Island is very poor. There are no trees nor native bushes — not even 

 the bushes which characterize the shore tracts of the most isolated coral 

 reefs of the Pacific are found there ; and yet some of the equatorial 

 counter currents must occasionally bring flotsam to its shores. We 

 collected a number of shore fishes and made a small collection of the 

 littoral fauna. The fishes have a decided Pacific look, and the few 

 species of sea urchins we came across are species having a wide distribu- 

 tion in the Pacific, 



While coaling, we spent some time examining the prehistoric monu- 

 .ments which line the shores of Easter Island. During our stay at La 

 Perouse Bay we visited the platforms studding the coast of the bay, and 

 made an excursion to the crater of Rana Roroka, where are situated the 

 great quarries from which were cut the colossal images now scattered all 

 over the island, many of which have fallen near the platforms upon which 



