316 I)E. G. J. HINDE. 



another group, subordinate as regards the amount of material contributed by it 

 collectively to the rock from the borings, comprises the remains, mostly fragmentary, 

 of sponges, echinids, annelids, Crustacea, polyzoa, ascidians, lamellibranchs, and 

 gastropods. 



These organisms are usually commingled together in the cores in various proportions; 

 very frequently we find, however, a preponderance of one or other of the principal 

 groups, such as foraminifera or corals, and occasionally of the calcareous algne, through 

 a variable thickness of the rock, one form continuing for a ])eriod and then gradually 

 giving way to the predominance or perhaps the exclusive occurrence of another. This 

 alternation i.s more noticeable in regard to the corals and foraminifera in the lower 

 part of the Main Boring, where the solid cores, for a thickness of sevei-al inches or even 

 of some feet, are largely composed of foraminifera, with here and there a small coral, 

 some calcareous algre, and an admixture of the cJehris of other organisms and fine 

 sediment, and then are succeeded by cores which consist mainly of corals with a 

 scanty number of foraminifera filling in the interspaces, and often a considerable 

 amount of Lrthoflicinniion and the drhi'i.s of the smaller organisms. There is no 

 regularity in the jieriod of the dominance either of corals or foraminifera, but on the 

 whole the foraminifera a])pear to contribute a notably larger amount of the rock than 

 the corals. Althougli the calcareous alg<ie form an important ])art of the rock in 

 various parts of the boring, they do nc^t, as a rule, so largely predominate in particular 

 portions as in the case of tlie groups just referred to, but they are more generally 

 a.s.sociated with corals. There are, however, some exce])tions. for some of the rock 

 coi'es in the upper part of the Main Boring are largely com})osed of branching 

 IJthothamnion, and the beds beneath tlie lagoon floor mainly consist oi' HaUmeda. 



The various orjxanisms from the boring's all belonij to existiny,' ii'enera, and with 

 some exceptions the species, as far as they can" be determined, are also still living. 

 The greater number have been recognised in the dredgings from the outer slopes of 

 the reef and from the lagoon, and in the collections made on the reef at Funafuti ; 

 some, however, have not yet been met with in the recent famia of the locality. 



In the following tables, lists of the genera of the various organisms present in the 

 borings are given, showing in one case their range of occui'rence, and in another their 

 distribution in the various cores. 



(7a) Notes on the Foraminifera from the Fttnafuti Borincjs. 



The abundance of the foraminifera, both in the solid rock-coi'es and in the loose 

 materials from the borings, indicates that they have taken quite as important a share 

 in forming the earlier stages of the reef as of tho.se no\v in progress. In some parts 

 of the Main Boring, where the rock has been largely altered by dolomitisation, their 

 walls have been broken down and partially obliterated, though not to the extent to 

 prevent recognition, b\it on the wliole their structures have l)een well preserved. The 



