1898] NOTES AND COMMENTS 223 



science, rather than children of the working hours. None the less, 

 we notice in the Bevuc liosc (1898, p. 116) that Prof. L, Ranvier 

 has made the comparison between the stimulation of crystallisation 

 by crystals and the regeneration of the membrane of Descemet. 

 Immediately under the cornea of the eye there lies a thin, tough 

 membrane named after Descemet. In embryological development it 

 arises as a secretion from a layer of endothelial cells lying next it on 

 the inner side. Prof. L. Ranvier has observed the process of its 

 reconstruction after operative or accidental interference. In such 

 cases, too, it arises as a secretion from the endothelial layer, but he 

 says the reconstruction begins around the edges of the undestroyed 

 portions of the membrane, and creeps only slowly to the centre of 

 areas over which the old membrane has been entirely lost. He 

 regards the process as showing that the edge of the undamaged 

 membrane stimulates the adjacent endothelial cells to the formation 

 of new membrane, as a formed crystal stimulates crystallisation. 



The Gkowth of Coral Islands 



We are not surprised to find that Dr John Murray holds a different 

 opinion as to the conclusions to be drawn from the boring on the 

 coral island of Funafuti from those which we expressed last 

 November. In a lecture to the Edinburgh Geological Society on 

 November 19th, Dr Murray maintained that the boring confirmed 

 his own theory. He has explained the presence of deep water 

 alongside coral reefs by the supposition that blocks of dead coral 

 fall down and form a steep-sloped talus on which living coral 

 can grow within the limit of depth necessary to its existence. The 

 boring on Funafuti is believed by Dr Murray to have been sunk 

 through such a talus. He lays stress on the admission that the 

 atoll has recently been raised about 4 feet, and that the reefs are 

 extending seawards. Those who are interested in this subject 

 should read what is said in our last number by Mr Charles 

 Hedley, who was the representative Australian zoologist on the 

 first expedition. 



We may also draw attention to a remarkably interesting letter 

 on the coral reefs of the Fiji Islands, communicated by Prof. 

 Alexander Agassiz to the February number of the American Journal 

 of Science. Prof. Agassiz, who has for some months been explor- 

 ing the Fiji Islands in company with Dr W. M'M. W^oodworth 

 and A. G. Mayer, considers that they do not present that strong 

 evidence in favour of the Darwinian explanation that J. D. Dana 

 and Darwin himself supposed. The shape of the atolls and of 

 the barrier reefs, he writes, " is due to causes which have acted 

 during a period preceding our own. The islands of the whole 



