Mr. C. P. Smyth on Tenei-iffe Fossils. 137 



is even or odd. Or separating the two cases, we find 



^^^^^^^{(l+0)«0^-(l+0)^0"}=0, a+ySeven, 

 and 



^"° ^)^"^ ^^ { (1 + 0)"0^+ (1+0)^0" + 2. 0"+^}=0, «+/8odd. 



1 have not attempted to verify a posierio)-i these elegant 

 formulse. 



2 Stone Buildings, W.C., 



June 18, 1859. 



XXIII. Teneriffe Fossils, and Sir Charles Lyell's Notice in the 

 Philosophical Maf/asine for July 1859. By C. PiAZZi Smyth. 



To the Editors of the Philosophical Magazine and Journal. 

 Gentlemen, Edinburgh, July 16, 1859. 



WITH some surprise I see, on page 21 of the Philosophical 

 Magazine for this month, that Sir Charles Lyell has 

 dragged into print a jmrtion of a private letter. 



While glad in any way to learn the scientific opinions of so 

 highly and deservedly esteemed an authority as the celebrated 

 author of the ' Principles of Geology,' I regret that I cannot in 

 this case agree with him, or allow that he has materially invali- 

 dated any essential part of my * Tenerifiie Report for 1856.' He 

 allows, for instance, that the important information there given, 

 of fossil shells having actually been discovered in Teneriffe, is 

 perfectly true ; but objects, first, to the discovery being spoken 

 of as " late," rather than " old ; " and secondly, to the locahty 

 being alluded to as " on the slopes of the great crater." Yet 

 with regard to the first objection, he does not give any earlier 

 printed authority than my own pages; and with reference to the 

 second, absolutely refuses all discussion of what it must depend 

 on, — under plea, too, of certain a priori opinions, which could not 

 have been shared in by the Royal Society Committee of June 

 1856, when they recommended to the Admiralty that "there are 

 also various points of interest relating to the geology and geo- 

 graphy of this region (Teneriff'e) which Prof. Smyth may possibly 

 find time to attend to." (See page 476 of pai-t 3 of Phil. Trans, 

 for 1858.) 



Sir Charles Lyell moreover alleges, at the very opening of 

 his communication, that my ' Report ' has been printed by the 

 Admiralty since the publication of a paper of his in the Phil. 

 Trans, for 1858, part 3. But as the last one, of the few pages 

 that were printed by the Admiralty, was worked off" on the -Uh of 



