22-i Reviews — The Atoll of F ana fati. 



Section vii is a short report of the dredging at Funafuti, by 

 Professor David, G. H. Halligan, and E. A. Finckh. 



In the lagoon seventeen out of eighteen dredgings were composed 

 of detrital Halimeda and fragments of shells intermixed with 

 a little seaweed. In the ocean living Halimeda only occurred 

 down to 45 fathoms, the limit of penetration of red and yellow 

 light. No pieces of an ancient coral-reef were dredged. 



The branching form of Litliothamnion was found only to occur 

 in shallow water. Thus it was thought that its presence in the- 

 cores might be of use in determining the depth at which dLXiy 

 particular piece was formed. However, Dr. Hinde is of opinioiv 

 that the exact form of Lithothamnion in the cores cannot be sati.s- 

 factorily determined, that is, whether the branching, nodose, and- 

 incrusting forms correspond with the similar growth-forms fronv 

 the reef-slopes. 



Section viii is a report on the lagoon borings by G. H. Halligan. 



Two borings were made at spots in the floor of the lagoon where 

 the depth at low water spring tides was 101 feet. The first passed 

 through 81^ feet mostly of Halimeda debris, next through 18 inches 

 of hard coral, o3 feet of coral fragments, 18 inches of coral, and, 

 finally, again through 26^ feet of coral material, thus in all 144 feet 

 beneath the floor of the lagoon, or 245 feet below the sea-level. 

 The second boring, a short distance from the first, went through 

 91^ feet of Halimeda debris, next through 8 feet of hard coral 

 with intermediate bands of softer material, and then entered coral 

 gravel and sand, to a depth altogether beneath the lagoon floor 

 of 94^ feet, or 196 feet below the sea-level. Mr. Halligan finishes 

 his report with the following words : — " It is perhaps only fair to 

 mention that the lagoon borings here described were undertaken 

 without the least idea of the formation to be expected, and were 

 carried out under the most unfavourable circumstances possible. 

 . . . . Had it not been for the co-operation and energy of the 

 captain, officers, and men of H.M.S. ' Porpoise,' the work could not 

 have been carried out at all." 



Section ix, by the same author as the last, describes the permanent 

 marks left by him on the island of Funafuti, to register for future 

 reference the present levels of difi'erent spots. These marks were 

 made of iron pipes let into the coral rock. 



Section x is the general report by Professor J. W. Judd, C.B., 

 LL.D., F.R.S., on the materials sent from Funafuti and the methods 

 of dealing with them. The cylindrical cores and fragments of 

 solid rock from the difterent borings were, on their arrival in 

 London, slit longitudiual]}^ and from those in the main boring to 

 a depth of about 800 feet from the surface a thin slab of the whole 

 size of each core was cut out of its middle. This slicing proved 

 a very arduous task, particularly in the nearly continuous solid cores 

 of the lower 400 feet of the boring, but it was very effectively done 

 by means of a lapidary's wheel driven by an electro-motor. The 

 slit surfaces of the hard cores when thus treated were sufficiently 

 well polished to allow of the determination of the larger organisms 



