Correspondence — Prof. Lehour. — Mr. Mellard Reade. 335 



Tafel XX.). My attention has been directed to this fact by a news- 

 paper report of a paper, recently read before the Geological Society 

 of Glasgow, by Mr. John Young, in which he identified, as one of 

 these " Kammplatten," an apparently allied relic from the Airdrie 

 district, and which, judging from that report, must either be the 

 same as Barkas's " Ctenoptychiiis " unilateralis, or closely related to 

 it. The two specimens, from which I drew up my description of 

 " Eiictenius" have no elongated process or "handle," but in other 

 respects there is an obvious general resemblance. 



I may take this opportunity of mentioning that within the last 

 few days I have obtained from the same ironstone a portion of a 

 small Labyrinthodont mandible, set with teeth which have the same 

 general configuration and markings as those of Messrs. Hancock and 

 Atthey's BatracMderpeton. E. H. Tkaquair. 



THE HUTTON COLLECTION OF FOSSIL PLANTS. 



SiK, — It has only within the last few days come to my knowledge 

 (indeed only to-day authoritativel}'), that the Hutton Collection of 

 Fossil Plants, at present deposited in the Museum of the Natural 

 History Society of Northumberland and Durham at Newcastle, had 

 been named by the Curator, Mr. Richard Howse, prior to the com- 

 piling by myself of a Catalogue of the Collection, published in 1878 

 by the North of England Institute of Mining and Mechanical 

 Engineers. The labels on the specimens, referred to in the Cata- 

 logue, were therefore Mr. Howse's, and not, as I until now imagined, 

 either William Hutton's original ones or mere copies of them. 



Moreover, an unsigned MS. List of the specimens in the Collection, 

 agreeing with the labels, with which I was furnished by the Mining 

 Institute, and which was used freely by me in drawing up the 

 Catalogue, must now be regarded as the result of much time and 

 labour spent by Mr. Howse in identifying and naming the whole 

 of the Hutton Collection. 



I trust you will allow me space in your Magazine to hereby 

 redress an injustice of which I was unaware at the time of its 

 commission. G. A. Lebour. 



College of Physical Science, 

 Newcastle-upon-Tyne, May 18, 188L 



SUBSIDENCE AND ELEYATION. 



Sir, — Mr. Starkie Gardner, in his paper on the above subject, in 

 the June Number of your Magazine, says (p. 245) : — "The records 

 of the Paleeozoic rocks point to a comparative uniformity in the 

 earth's surface in remote times, there being neither evidence of 

 great depths in the sea, nor of mountainous elevations of the land." 



The latest calculation of the average depth of the sea is a little 

 over two miles. The area of land being, roughly speaking, about 

 one-third of that of the oceans, it follows that if the solid part of 

 the earth were a perfect sj^heroid, having neither depression nor 

 elevation, it would be covered by an universal ocean nearly one and 

 a half miles deep. Is there, therefore, any meaning in saying that 

 there ever was a time when great depths of the sea did not exist? 



