256 DE. G.:J. HINDE. 



Depth from Surface, 822-833 feet; Distance Bored, 11 feet; Total Length of Core 

 Ohtained, 7 feet 11 inches; Numbers of Co )^s, 198a-215a. 



The cores in this portion of the boring are for the most part cyhndrical, in one or 

 two instances, however, the rock has broken up into fragments, now rounded by the 

 drill. The cores are mainly of a whitish to cream-tinted or greyish -white, porous, 

 dolomitic limestone, for the greater part soft ; though it does not as a rule yield to the 

 finger nail, it is readily scratched by a knife. Other portions are much harder, 

 only scratched by a knife under pressure ; both hard and soft portions are found in the 

 same piece of core. The pores and larger cavities are lined by deposits of dolomitic 

 limestone, in very thin successive layers, which in section have the appearance of 

 agate or stalactitic structure. There is also an efflorescence on the exterior and split 

 surfaces of some of these cores which yet further obscures their characters. Corals 

 are only occasionally present and then merely as indistinct casts or impressions of the 

 outer surface ; small examples of Pocillopora, Madrepo7'a, and Astrceopora are the 

 only forms noticed. The rock, as seen in microscopic sections, consists principally 

 of a fine sediment with foraminifera and minute fragments of organisms. The 

 foraminifera belong for the most part to Carpentei'ia, Polytrema, which often forms 

 nodules, Amphistegina, and Heterostegina, while Glohigerina, Planorhulina, and 

 Calcarina are of less frequent occurrence. Carpenteria in these cores has the walls 

 preserved and shows the minute structure favourably. The cores further contain 

 large echinid spines, casts of lamellibranchs and gastropods, Halimeda and 

 Lithotliamnion. 



Details. 



(198a). Length .33 millims. Several rubbly pieces of greyish-white, hfirrl dolomitic rock, in which only 

 obscure casts of corals and Atuphistegina can be distinguished. 



(199a). Length 110 millims. Cylindrical, whitish, soft and porous, efflorescent, with some hard grew 

 areas where coral casts have been infilled with crystalline dolomite. Mitdrepora (?). Core mainly of detrital 

 sediment with Carpenfcrui, numerous echinid spines, and small lamellibianchs and gastropods. 



(200a). Length 92 millims. Core similar to preceding. 



(201a). Length 71 millims. Whitish, hard, mostly compact. Cast of perforate coral filled in with 

 dolomite. Core mainly of fine sedimentary material with Polytrema pluiutm, Aiiiplnsfcgimi, and numerous 

 echinid spines, some retaining a pinkish tint and obtusely triangular in transverse section. 



202a. Length 308 millims. AMiite to greyish-white, banded, porous, in part soft, in part hard. 

 Efflorescence in places. Several irregular cavities in which corals were probably present, but only one, an 

 impression of Pocillopara, could be distinguished. The core mainly of detrital materials with undulating 

 layers of Polytrema planum, Ainphidegijui, and Heterostegina. Echinid spines and casts of gastropods. 



(203a, 204a) [586]. Total length 163 millims. Whitish, chalky-looking, porous, dolomitic rock, in 

 places sufficiently soft to be scratched by the finger nail, and with occasional cavities, which may originally 

 have contained corals, but there are no indications left. The core is principally of fine sediment, 

 conta.ming' Glohigeriv/i, PlanmMina, Carpenteoia, Polytrema planum , and Amphistegina. Echinid spines. 



(205a) [738]. Length 68 millims. Greyish-white, banded, hard, cavernous rock. In the central portion 

 of the core, cast of an upright branching Madrepora replaced by dolomite, with the coral interstices infilled 



