14 bulletin: museum of comparative zoology. 



mencing with the older, a series of rocks which, excepting the oldest, 

 conform to the same dip and strike. They comprise a vast group of 

 Limestones and so-called " Fiji soapstones " that form the nearer coastal 

 scarps, reaching in places to a height of 330 feet above the sea. The old- 

 est of these Singatoka rocks is a compact bedded blue and apparently 

 non-fossiliferous limestone having a high dip (50°) (Plate 3, Fig. 1). 

 To this succeeds a series of soft rocks having an average dip of 15° 

 (Plates 7, 33). The junction of this highly inclined blue lime- 

 stone with the softer overlying sti'ata could not be distinctly seen 

 (Plate 32). The next group of strata in ascending order is undoubt- 

 edly large and comprises a sandy species of limestone. This gives 

 place to a shelly and foraminiferal zone ; another series contains fossils 

 of Pecten and other lamellibranch types, with here and there a stra}-, 

 weathered, indeterminable coral (Plate 3, Figs. 1, 2). Still another 

 series comprises a dense, homogeneous, macroscopically non-fossiliferous 

 zone, and this includes a six-foot belt of coral reef, containing Porites 

 or Monti pora. This, in turn, overlays a two-foot belt of red clay, and 

 the top of the reef consists of a thin belt of finely laminated lime- 

 stone. To this succeeds a great development in layers of a brown, 

 friable rock that will scarcely bear the weight of the hammer (Plate 3, 

 Figs. 1, 2). A gap in the section occurs at this spot, due to drift 

 sands of later origin hiding the underlying rock : but two or three miles 

 toward Thuvu similar layers of fossiliferous limestone are again picked 

 up, and in these occurs a belt of hard red limestone. 



At Thuvu the limestone has disappeared and its place is taken by 

 hills 200 to 300 feet high of inclined " soapstone " (Plate 4). 



The series of friable and dense limestones just considered lies back 

 about two miles from the sea, the Singatoka having deposited its enor- 

 mous flat seawards in front of it so that the cliffs abut directly on 

 it. On the seaward of the lower limestone formations and of the old 

 Singatoka flat a modern elevation has exposed a reef wall in places as 

 much as twenty to twenty-five feet above high-water mark (Plate 5). 

 This reef face is vertical. 



"The Lau Group" and the Smaller Islands. 1 



These may be divided for purposes of classification, as has been done 

 before, into : The volcanic islands ; The limestone islands ; The volcanic 

 and limestone islands. 



1 See A. Agassiz, /. c, p. 17. 



