REPORT ON IMATERIALS FROM THE BORINGS AT FUNAFUTI ATOLL. 259 



lens; the rock almost entirely fotuniinifenil and detrital ; the pores arc lined with the inanniiillary 

 crystalline material. 



(229a) [745]. Length 149 millim.s. Greyish-white, hard, partly compact, partly porous, very uniform, 

 dense rock, similar to the preceding core. A microscopic section shows the same foraminifera 

 and detrital materials cemented by calcite (1) as in the cores above. Orhifolites, Carpenteria., Calcarina, 

 Gypsina, Polylrema plamim, Ainpliidegina and Heferosfeyina. Alcyonarian spicules. Echinid spines. Litho- 

 thamnion: 



(230a) [746]. Length 223 millims. Greyish-white, compact mostly, very uniform, dense rock, 

 apparently a limestone, only in part dolomitic. Corals not recognised. Very little to be seen with 

 a lens ; a microscopic section from the lower half of the core shows numerous alcyonarian spicules 

 in good preservation, mingled with Polytrema mmiaceum, Amphistegina, and Heterostegina. Echinid spines. 



(231a). Length 221 millims. Greyish, mostly compact, hard, dolomitic limestone. Obscure traces 

 of corals, now replaced by the crystalline mammillated deposit, a small Orhkella (1) and Madrepm-a. 

 Hardly anything to be made out with a lens, the structures being replaced by crystalline material. 

 Lithothamnion {1). 



(232a). Length 105 millims. Grey, with white patches, very hard, mostly compact rock, some 

 small corals, for the most part replaced mth solid crystalline dolomite. Astrcea (1), Madrepora (V), 

 also cast of Millepora, which has not been replaced, and is better preserved than the ordinary corals. 

 Foraminifera not recognisable with lens. Lithothamnion occurs as white patches. Cast of lamellibranch. 



(233a, 234a). Total length 245 millims. Greyish-white, mottled and speckled, compact to porous, 

 dense. Indications of corals, now replaced by crystalline materials ; they appear to have formed a 

 considerable part of these cores. The coral areas enclosed by Lithothamnion. Very little to be seen 

 beyond a few specimens of Orbitolites, Amphistegina, alcyonarian spicules, and echinid spines. 



Depth from Surface, 844-853yt'e^ ; Distance Bored, 9 feet ; Toted Lengtlt of Cores 

 Obtained, 7 feet 2 inches; Numbers of Cores, 235a-248a. 



Cores cylindrical, of grey, greyish- white, and whitish limestone, in part dolomitic. 



The rock hard, generally compact, hut in places porous and cavernous. For about 



2 feet in the upper part of this boring the rock contains numerous casts of small 



corals, in the remaining 7 feet the rock consists principally of fine detrital material, 



with foraminifera, and only occasionally casts of small corals. The corals are very 



unfavourably preserved, the only forms recognised belong to Focillopora, Astrcea, 



OrbiceUa, and Madrepora. Alcyonarian spicules are plentiful, and generally 



distributed throughout the cores. The foraminifera include OrbitoUtes, Carpe7iteria, 



Calcarina, Gypsina, Pohjtreina, Anip>histegina, and Heterostegina. Halimeda and 



Lithothamnion. 



Details. 



(235a) [747]. Length 77 millims. Grey, hard, mostly compact, dolomitic limestone. Cast of an 

 Astrsean and of some perforate corals, now infilled with the crystalline matrix. Greater part of core 

 of minute organic detrital materials, with OrbitoUtes, Carpenteria, Calcarina, Gypsina inhcerens, Pohjtrema 

 mmiaceum, P. planum, Amphistegina, and Heterostegina. Numerous alcyonarian spicules, less favoiu-ablj- 

 preserved than hitherto ; some are partially replaced by the crystalline matrix. Halimeda and lAtho- 

 thwmnion. 



(236a). Length 138 millims. Grey, hard, minutely porous. In lower part of core cast of Madrepora 

 contecta. Alcyonarian spicules very numerous. But little to be seen with lens. 



2 L 2 



