REPORT ON MATERIALS FROM THE BORINGS AT FUNAFUTI ATOLL. 211 



as those of Core No. I-tG. Calcite now fills in the iiitorspiices between the spicules. The stem is 

 penetrated l)y holes made hy boring organisms in the same way as in an ordinary coral, and the fine 

 sediment infilling the borings contains Truncatuliim and Amphidcgina. 



(152-1.56). Irregular nodular pieces of greyish-white porous rock having a total length of 151 millims. 

 They are apparently composed of fragmental materials, Init hardly anything beyond detached alcyonariau 

 spicules can be recognised with a lens. 



(157). Length 83 millims., by 79 millims. in width. Cylindrical core of porous greyish-white rock with 

 cavities from which organisms have l)een dissolved out. The greater part of the core is fragmental, but 

 there are in it casts of small examples of Sfylophora. Echinid spines. 



(158) [643]. Length 100 millims. Greyish-white, porous, and cavernous rock similar to preceding. 

 Pi'incipally fragmental, smtxll pieces of Pocillopora are, however, present. In a microscopic section the 

 following forminifera can l)e recognised : Globigerina (rare), Carpenteria, Polytrema miniaceum, P. pilanum, 

 G!ipsina,-A\\i\Amp]dxtcfiino. Echinid spines and plates. The fragments are cemented into a hard rock by 

 finely granular calcite. In some of the cavities laid open by slitting the core, there is fine white powdery 

 material either loose or lightly consolidated. 



Depth from Surface, 1 90-200 /ec^; Distance Bored, 10 feet ; Total Length of Core 

 Obtained, A feet 8 inches; Numbers of Cores, 159-175. 



The solid cores of this 10 feet of the boring, taken together, reach to nearly one-half 



of the distance bored. The cores are for the most part cylindrical, usually cavernous, 



and also with numerous irregular holes or pores and small slit-like hollows. The rock 



is a greyish-white moderately hard limestone, readily scratched by a knife. Very 



little can be distinguished with a lens, beyond that it appears to be fragmental in 



character and similar to the rock cores from the preceding 40 feet of the boring. 



Microscopic sections show that it consists principally of foraminifera, many of them 



broken up into small fragments, and of echinid spines. The only indications of corals 



are casts of Stylophora, Orbicella, and small pieces of Heliopora ccerulea in very 



imperfect preservation. Possibly some of the now empty cavities may have originally 



contained corals, but if so, no traces of them remain. The corals form but a very 



small proportion of this 10 feet of the core. Some of the cavities contain white 



unconsolidated powder. The rock appears to be mainly a fine organic sediment 



with foraminifera, now cemented by calcite, in which corals are somewhat rarely 



present. 



Details. 



(159) [525, 526]. Length 150 millims. Cylindrical, with cavities, where unconsolidated materials have 

 been removed. Microscopic sections show the following foraminifera : Discorbina, Truncatidina, Globigerina, 

 Carpenteria, Polytrema miniaceum, P. planiun, Gypdna, Amphistegina, and Heterostegina. Echinid spines 

 plentiful, their structure fairly well shown. The foraminifera less favourably preserved than in higher 

 sections. The finer particles of sediment apparently without structure. 



(160). Length 75 millims. General characters similar to preceding. Imperfect cast of Heliopora 



ceerulea. 



(161-165). Cylindrical cores of the same greyish-white cavernous and porous rock as the preceding, with 

 a total length of 272 millims. Casts of Heliopora cm-uleu are the only organisms recognisable with a lens. 



(166) [644]. Length 230 millims. Cylindrical core ; rock similar to the preceding. Fragment of cast 



2 E 2 



