290 NATURAL SCIENCE [November 



Prof. Edgeworth David may therefore be congratulated on 

 having finally proved conclusively the truth of Darwin's brilliant 

 theory. It may be objected that it is too soon to shout, as the 

 cores have not yet been subjected to microscopic examination, and 

 that one boring is not sufficient. But neither objection is worth 

 much. Coral-reef rock is of very varying composition ; the coral 

 grows in hummocks separated by more or less narrow spaces, which 

 are filled up by coral sand, broken shells, foraminifera, &c. Micro- 

 scopic examination of fragments of limestone broken from coral reefs 

 sometimes shows no trace of coral. Coral, moreover, is more readily 

 decomposed than shell sand or foraminiferal limestones. Hence it 

 will not be surprising if most of the slices cut from the deep core 

 shew no trace of coral structure. But that will not prove that they 

 are not to be regarded as reef rock. Nevertheless it is to be hoped 

 that some parts of the limestone from the bottom of the core will be 

 sufficiently well preserved to show the nature of its formation. 



To the objection that one boring is not sufficient to prove a 

 theory proposed for so many islands, it is only necessary to point 

 out that Darwin himself insisted that his theory was not universal. 

 He never intended it to apply to the coral reefs of the West Indies, 

 the Eed Sea or the Persian Gulf. What the Funafuti boring has 

 proved is that the subsidence method is possible ; and if one island 

 in the Ellice Archipelago is sinking, it is probable that the other 

 islands in that group are also doing so. No doubt some cases will 

 be found in the Pacific of coral islands formed on banks left by 

 denuded volcanoes. But the arguments which Darwin used to show 

 the improbability of many of the atolls having been formed in this 

 way are still valid ; and they are strengthened by the demonstration 

 in the only atoll yet tested, that the basis is a block of subsided 

 reef limestone. 



There is some zoological evidence in support of a former migra- 

 tion of land animals across the area now occupied by the coral sea ; 

 and naturalists are now at liberty to explain their distribution by 

 the former existence of land in that area. 



The persistence with which the Australian naturalists have 

 persevered in their attempt to settle this controversy, and the skill 

 with which Prof. Edgeworth David has overcome the mechanical 

 difficulties, are worthy of the highest praise. 



The Temperatuees of Eeptiles, Monotremes, and 



Marsupials 



Several other interesting contributions have reached us this month 

 from the Antipodes, and among the most valuable may be noted an 

 account of some new experiments on the body-temperature of verte- 



