Watts and Newton — Rocks from Solomon Islands. 359 



(6) 30-35 per cent, of Ca C 3 , pteropods, gasteropods, lamelli- 



branchs, foraminifera, etc. 



(c) 60 „ ,, fragments of corals, algoe, lamelli- 



branchs, and a few foraminifera. 



(d) Coarse rocks made of fragments of volcanic and coral rocks 



in rounded grains. 



B. Organic constituents most abundant, G6-96 per cent, of Ca C 3 ; 



volcanic materials quite subsidiary. 



(e) Coral rocks with the original structures more or less 

 obliterated, becoming drusy, saccharine, or compact. 



(/) Coral rocks with alga?, fragments of mollusca, corals, and 



ecbinoderms; interstices filled with foraminifera and small 



calcareous organisms. 

 (g) Fawn-coloured, crystalline limestones made of the coral 



ooze of lagoons. 

 (/«) Chalk-like coral limestones ; corals, mollusca, algae, etc. 

 (i) Foraminiferal limestones chiefly made of the tests of pelagic 



and bottom-living foraminifera. 



C. A deep-sea clay. 



The greater part of Lieut. Waugh's collection falls into these 

 classes, as will be seen from the following account of the chief 

 specimens. 



A (a) Foraminiferal mud. — South coast of Tetapari Island (F. 303), 

 " from between the blocks of coral." This resembles the earthy 

 foraminiferous deposit described from Ugi and Treasury Islands by 

 Dr. Guppy. It consists of fine argillaceous material, a few chips of 

 volcanic minerals, and abundant foraminifera, some cells of which 

 are empty, but others filled with a brown deposit insoluble in 

 acid. On dissolving the tests in weak acid an earthy skeleton 

 would sometimes persist for a moment, as though the perforations 

 had been filled with some fragile, insoluble substance. A few 

 sponge spicules were seen in the residue. Mr. Newton says that 

 Globigerina is the most abundant foraminifer. 



B (e) Coral rocks are of very common occurrence in New Georgia, 

 and have been collected from the following localities on that and the 

 neighbouring islands — Viru harbour, the south coast, Bili village, 

 and Mbulo Island. They also occur on Ugi Island and on the main- 

 land of Florida Island. They were found at the sea-level as well as 

 at heights up to 130 feet, and as much as a mile inland. They 

 correspond to Dr. Guppy's description, and need no further remark. 



B (/) These might be called " mixed coral rocks." They are clastic 

 limestones made up of broken bits of organisms, calcareous mud, 

 and a small amount of terrigenous or volcanic material. They occur 

 on the mainland of Florida Island, one at the water-level (F. 278), 

 the second at 20 feet (F. 281), and the third at 40 feet, above it 

 (F. 279), on the floor of a cave 20 feet below the surface on the 

 island of Ereru, inside the lagoon (F. 272), and at the Charapoana 

 entrance of the great barrier reef of New Georgia (F. 290). I 

 append Mr. Newton's description of the rocks — 



