278 



ALliATROSS" TROPICAL PACIFIC EXPEDITION. 



We made a number of soundings from south of Nurakita towards the 

 Marshall group ; ' these, in addition to those of the " Penguin," clearly show 

 that the Ellice Islands are isolated peaks (PI. 2'Jl) rising from considerable 

 depths (from 1500 to over 2000 fathoms), and that the same is the case with 

 the Gilbert Islands (PI. 223); Maiana, Tarawa, and Apaiang however being 

 summits of a secondary plateau with greatest depths of 413 fathoms 

 (PI. 223). The thirty soundings we made between the atolls of the 

 Marshalls (PI. 225) ^ indicate that they also rise as independent peaks or 

 ridges, with steep slopes, from 2000 to 2500 fathoms. The atolls are not 

 connected by a great plateau or a broad ridge as would seem to be indicated 

 by the trend of the atolls in two parallel lines, forming the two sides of 

 • the Marshall Islands group. The parallel chains of atolls of the Marshalls, 



the Ralick, and the Ratack are really 

 only the summits of isolated peaks 

 rising but a few feet above the sea 

 level. The soundings between Elmore 

 and Namu are not as deep as between 

 other atolls of the group ; they indi- 

 cate a connecting ridge with a great- 

 est depth of less than 1100 fathoms 

 (PI. 225). Between Rongelab and 

 Ailinginae even shallower water is 

 indicated. The Gilbert and the Mar- 

 shall Islands are separated by great 

 depths, over 2500 fathoms. South 

 of Nurakita towards Fiji no depths 

 greater than 2000 fathoms have as yet been reported (PI. 221). The 

 Marshall, as well as the Ellice and Gilbert Islands, seem to be somewhat 

 higher than the Paumotus ; but this difference is only apparent, and is due 

 to the difference in the height of the tides ; it is very small in the Paumotus, 

 while in the former groups it may be five and even seven feet. 



After leaving Arhno, our soundino;s indicated that we had struck the 



Maksiiall Island C.vnue, Wotje. 



1 Mem. M. C. Z. XXVI., No. 1, Prel. Rep., p. 61, Stations 194-207, 1902. 

 ^ Loc. cit.. Stations 208-237. 



