258 



THE GEOLOGIST. 



the first instance, by able naturalists to the Chelonese, Fish, 

 Crustaceans, and even Coleoptera. 



M. Agassiz proceeded to notice the researches of Dr. Mal- 

 colmson, Mr. Alexander Robertson, and especially the late 

 Lady Gordon Gumming, who had collected these remains 

 and distributed them amongst geologists with the greatest li- 

 berality. Lady Gumming had studied the remains with 

 great care, and prepared a series of drawings of all the most 

 perfect specimens with a precision of detail and artistic ta- 

 lent, which few naturalists could hope to attain. The col- 

 lections of Lord Enniskillen and Sir Philip Egerton had 

 also furnished him with many beautiful specimens, and Dr. 

 Traill and Mr. H. E. Strickland had considerably increased 

 the number of species by their examination of the Orkney 

 schists. In the southern part of Scotland, Prof. Jamieson 

 and Mr. Anderson had collected the species belonging to the 

 upper part of this formation, several of which were figured 

 by Mr. Anderson in his ^ Memoir on Fifeshire.' The dis- 

 tant excursions of Mr. Murchison enabled the author to ex- 

 tend his Report to fossil fish of the same age found in Rus- 

 sia, but perfectly identical with those of Scotland. The 

 continental researches of M. Omalius d'Haloy and M. Hae- 

 ninghausen had also brought to light scales of fish belonging 

 to this formation. M. Agassiz then presented some general 

 considerations on the characters and geological distribution 

 of the fossil fishes found in these strata, first observing, 

 that in examining these remains he had employed the method 

 established by Guvier — of comparing them with each other 

 and with living species. Wherever this principle had been 

 adhered to, it had given results which had suffered scarcely 

 any modification by time. He first remarked, that all spe- 

 cies and nearly all the genera of fish found in the Devonian 

 strata were entirely confined to them, neither extending 



