254 W. Danes — On Saurocephalus. 



cliemical agency. By the action of eartli-heat and other causes, 

 however, some of these rocks have been so altered that their original 

 source is scarcely, if at all, recognizable. How this earth-heat has 

 raised the strata, thus formed beneath the sea, above the waters of 

 the ocean, has been pointed out; and the action of the sea- waves, 

 and of rain and rivers in carving out the face of the country, 

 horizontally and vertically, has been indicated. In tracing the 

 chain of causation from the well-known to the Unknowable, I have 

 not followed the example set by Prof. Huxley in the excellent little 

 book which bears the same title as this article. In these days, how- 

 ever, when we hear so much of the " pride of Science," it is well to 

 point out that in the study of Nature we reach at last ultimate questions, 

 with respect to which we must one and all confess with modest 

 humility that we are and must be ignorant. Finally, in making 

 each fact the effect of one which had gone before it, in time, and the 

 cause of one which followed, I have aimed at that organization of 

 knowledge, without which any number of accumulated facts are but 

 isolated pieces of general information. 



II. On the Nomenclature of Saurocephalus lanciformis of the 



British Cretaceous Deposits : with Description of a New 

 Species {S. Woodwardii). 



By "William Daties, F.G.S., 



of tlie British Museum. 



(PLATE VIII.) 



DE. MANTELL, in his classical work, the " Fossils of the South 

 Downs," figured two large compressed and lanciform teeth ^ 

 preserved in his collection and obtained from the Chalk at Lewes, 

 as respectively the teeth, of an unknown fish and of a species 

 of Squalus. Similar teeth, and from the same collection, were 

 subsequently figured and described by Prof. Louis Agassiz,^ who, 

 from external characters chiefly, considered them to have belonged 

 to a Sphyr^noid fish, and he referred them to an American 

 species founded by Dr. Harlan upon portions of jaws with teeth 

 in situ found in a Cretaceous deposit in the State of New Jersey, 

 but described by him^ as remains of a Saurian, and to which he 

 o-ave the name of Saurocephalus lanciformis. At the time when 

 Agassiz referred these teeth to Harlan's species, and determined 

 their ichthyic character, he had not seen the American fossils ; but 

 he states that these conclusions were subsequently confirmed by 

 Prof. Owen's description and drawings of the microscopic structure, 

 and of teeth of the natural size of the Saurocephalus lanciformis, 

 Harl., in his " Odontography," p. 130, pi. 55. But Prof. Owen's 

 researches were made upon a genuine tooth of the American fossil 

 sent to him by Dr. Harlan, and not upon an English specimen. 

 For some years after the publication of Agassiz's work the species , 



^ op. cit. pi. 33, figs. 7 and 9. 



2 Eecherches Poissons Fossiles, torn. v. p. 102, pi. 25 c, figs. 21 — 29. 



3 Journ. Acad. Nat. Sc, vol. iii. p. 337, pi. xii. figs. 1—5. 



