GEOLOGY AND MINERALOGY. 24& 



of curious bodies, each of which was surmounted by a depressed, 

 enamelled, thorn -like spine or tooth, in some cases with points as 

 sharp as that of a coarse needle ; these the author supposed to be 

 spinous scales, belonging to several new species of fish, allied to the 

 Squaloraia, and that to the same genus were to be referred a number 

 of hair-like spines, with flattened fluted sides, found in the same 

 deposit. 



There were also present specimens, hitherto supposed to be teeth, 

 and for which Agassiz had created the genus Ctenoptychius, but 

 which he was rather disposed to consider — like those previously 

 referred to — to be the outer scales of a fish allied to the Squaloraia. 

 It was remarked that, as the drift must have been transported from 

 some distance, delicitte organisms could scarcely have been expected ; 

 but, notwithstanding, it contained some most minute fish-jaws and 

 palates, of which the author had, either perfect or otherwise, 130 ex- 

 amples. These were from a quarter to the eighth of an inch in length, 

 and within this small compass he possessed specimens with from thirty 

 to forty teeth ; and in one palate he had succeeded in reckoning as 

 many as seventy-four teeth in position, and there were spaces where 

 sixteen more had disappeared, so that, in this tiny specimen, there 

 were ninety teeth ! 



Of the order Eeptilia there were probably eight or nine genera, 

 consisting of detached teeth, scutes, vertebra?, and ribs, and articu- 

 lated bones. Amongst these he had found the flat crushing teeth 

 of the Plaoodus : a discovery of interest, for hitherto this reptile had 

 only been found in the muschelkalk of Germany, — a zone of rocks 

 hitherto wanting in this country, but which, in its Fauna, was 

 represented by the above reptile. But by far the most important 

 remains in the deposit were indications of the existence of triassic 

 mammalia. Two little teeth of the Microlestes had some years 

 before been found in Germany, and were the only traces of this high 

 order in beds older than the Stouesfield slate. The author's minute 

 researches had brought to light fifteen molar teeth, either identical 

 with or allied to the Microlestes, and also five incisor teeth, evidently 

 belonging to more than one species. A very small double-fanged 

 tooth, not unlike the oolitic Spalacotherium, proved the presence of 

 another genus ; and a fragment of a tooth, consisting of a single fang, 

 with a small portion of the crown attached, a third genus, larger in 

 size than the Microlestes. Three vertebrae, belonging to an animal 

 smaller than any existing mammal, had also been found. 



The author inferred that, if twenty-five teeth and vertebra;, 

 belonging to three or four genera of Mammalia, were to be found 

 within the space occupied by three square yards of earth, that 

 portion of the globe which was then dry land, and from whence the 

 material was in part derived, was probably inhabited at this early 

 period of its history by many genera of Mammalia, and would serve 

 to encourage a hope that this family might yet be found in beds of 

 even a more remote age. A discussion followed, in which Sir C. 

 Lyell, Professor Sedgwick, Dr. H. Falconer, and others took part, 

 when the importance of the author's discoveries was recognised. 



