REPORT ON MATERIALS FROM THE BORINGS AT FUNAFUTI ATOLL. 217 



From 370 to 373 feet. Sample of fine powdery material, with angular and partially roiitided chips of 

 greyish rock up to 7 millims. across. Fragments of I'ociUo/wra common, also pieces of polyzoa. A 

 microscoiDic section [843] of some of the larger chips of the white rock showed that it consisted 

 of sediment, with entire and fragmentary foraminifcra, also pieces of coral showing minute structure. 

 The foraminifera ii\clude Curpenfcrla, J'oli/fn'iiiu i/iiniaceuin, P. jihinmii, TiintiKintx hariilalas, Calcarina, and 

 Ainphixfpgina. 



Depth frorn Surface, S7S-S7Sfeet; Distance Bored, 5 feet ; Total Length of Core 

 Ohtcnnecl, 1 foot 9 inches; Numhers of Cores, 199-206. 



These are the first soHd cores, with the exception of a fragment about an inch in 

 diameter, which have been obtained from the boring in a distance of 143 feet ; that 

 is, from a depth of 230 feet to 373 feet, only loose, broken-up small fragments of 

 rock, or so-called sand, reached the surface. The cores from the present 5 feet of the 

 boring are cylindrical, of a hard, compact to minutely porous limestone, whitish-grey, 

 with numerous faint pinkish spots (foraminifera) and occasional hollows where corals 

 have been partially removed. The rock is composed principally of corals and 

 foraminifera with broken branching Lithothamnion. There is some amount of fine 

 sediment, very little altered beyond consolidation. The different components are 

 cemented together by a calcite matrix. The corals present belong to Pocillopora, 

 undetermined Astrseans, Madrepora contecta, and Porites ; they are all in the 

 condition of casts, the original structures having been dissolved away for the most 

 part, or replaced either by calcite, or a fine powdery material. The foraminifera 

 form, perhaps, a larger proportion of the rock than the corals ; they principally 

 consist of Orhitolites and Amphistegina Lessonii. The latter is very abundant, 

 the rock in places being filled with them. Other organisms are echinid spines, 

 stellate ascidian spicules, now replaced by calcite and casts of small gastropods, the 

 shells being entirely removed. 



The rock of these cores is harder, more compact, and less porous and granular than 

 that of the cores between 170 and 230 feet, and the foraminifera and Lithothamnion 

 in it are in a much better state of preservation. 



Details. 



(199). From 373 to 378 feet. Length of specimen 25 millims. A nodular piece of hard grey rock, 

 consisting of Orbifolifes .nud Amplmfegina, with fragments of Lifliothamnion cemented l^y calcite. 



(200). From 373 to 378 feet. Length of specimen 65 millims., breadth 54 millims. Core cylindrical, 

 principally of corals; casts of Pocillopora. An Astrsean coral poorly shown, and Madrqjora conteda. 

 Microscopic sections of the corals [531, 532, 532a] show that the fibrous structure is partly retained 

 in Pocillqwra, though much altered ; in the Madrepora it has been either removed or replaced by calcite ; 

 the original interstices of the coral are in part infilled with fine organic sediment, now consolidated, or 

 with crystalline calcite. The foraminifera present belong to Orhitolites, GloUgerina, Carpjenteria, Polyirema 

 miniacewn, P. planum, Gi/pmna, Calcarina, and Awphistegiiia. Casts of gastropods. Lithothamnion. 



(201). From 373 to 378 feet. Length of specimen 55 millims. Core rounded, hard, somewhat porous. 



2 F 



