Secondary Rocks. 561 



glad that our old and valued associate is once more before the pub- 

 lic with one of those original researches with which, during the last 

 twenty-five years, he has so much enriched our science, and which 

 have obtained for his name so high a place in the volumes of the 

 great Cuvier, as to render any eulogium on my part superfluous. 

 Valuing as I do the arduous labours of a man, who, liiie Dr. Mantell, 

 has occupied the few leisure hours at his disposal, first in discover- 

 ing, next in dissecting from their stony bed, and lastly in describing 

 the specimens ; I am bound to observe that such merits deserve, as 

 they have obtained, the highest praise which working geologists, like 

 ourselves, can offer. In thus estimating, however, the value of Dr. 

 Mantell's researches, I must be permitted to say (and in the most 

 friendly spirit), that whilst I understand the propriety of the motive 

 which led him to communicate his last memoir on the Iguanodon 

 to the same Society to which he had addressed his first account of 

 that Saurian, I regret that he should not have communicated to our- 

 selves other palseontological memoirs, the consideration of which, I 

 must say, pertains particularly to the Society over which I preside. 

 So long as the Royal Society produces volumes adorned by the 

 writings of the first mathematicians, physiologists, and chemists of 

 the age, so long will it maintain its high place, little heeding our 

 humbler pursuits. 



Two memoirs have been read before us to illustrate the celebrated 

 " bone-bed," which, lying at the base of the lias, and in contact with 

 the uppermost members of the new red system, has hitherto been 

 classed with the former deposit. The first of these, communicated 

 by Sir Philip Egerton, is entitled " On the occurrence of Triassic 

 Fishes in British Strata;" the second is " On the occurrence of the 

 Bristol Bone-bed in the Lower Lias, near Tewkesbury," by Mr. H. 

 Strickland. The fact to which Sir Philip Egerton adverts is, that out 

 of a series of specimens from this bed atAxmouth and Aust, M. Agas- 

 siz determined four species to be well-known forms of the Muschel- 

 kalk, whilst fifteen were unknown in that deposit or any other part 

 of the triassic group ; and Sir Philip concludes, that the beds in 

 question ought to be removed from the lias, not only because the 

 fishes are specifically distinct from those of that formation, but be- 

 cause the forms of the ganoidians possess the heterocerque tail, a 

 form which the classification of Agassiz confines to deposits of 

 higher antiquity. This reason ought to have great weight, and 

 might, if unconnected with others, at once dispose us to move our 

 base line of the lias some few feet higher. 



A fresh-cut section of the Gloucester railway had exposed at Combe 

 Hill, near Cheltenham, the same singular bone-bed which is so well 

 known at Axmouth and at Aust. From an intimate knowledge of 

 that country, I can recognize the fidelity with which Mr. Strickland 

 identifies certain thin layers of sandstone and grit at the bottom of the 

 lias extending to the nortli witli the adjacent bone-bed, which in its 

 furth(;r extension losers those ichthyolite ciiaracters lor which it is so 

 remarkable over an area in our isles as wide, indexed, as tiiat of the 

 famous " Kiipfer Schiefer" inGermany. Now in Gloucestershire tlic 



