Miscellaneoits. 103 



between them, so that, in all probability, this will prove to be a 

 distinct species ; but this I hope Mr. Darwin will be able to de- 

 termine. 



Another and probably a diflFerent species has been found by Mr. 

 Gavey at Chipping Campden in Gloucestershire, in the top beds of 

 the lower Lias, which are very prolific in organic remains wherever 

 they occur. As the Cirripedes are usually rare in a fossil state, 

 especially in the Oolites and Lias, it seemed desirable to notify the 

 existence of some species of Lepadidae during these geological periods, 

 — a somewhat earlier date than the one previously indicated. 



MR. YARRELl's collections. 



Our readers will be gratified to learn, that the Trustees of the 

 British Museum have secured for the Museum the collection of British 

 Fish, and all the specimens of Birds and other animals illustrating 

 Mr. Yarrell's various papers in the Transactions of the Linnsean and 

 Zoological Societies, at the sale of his property. 



On the Stereognathus Ooliticus, from the Stonesjield Slate. 

 By Prof. Owen, F.ll.S., F.G.S. 



The subject of this paper was a small mammal, represented by a 

 fragment of a lower jaw retaining three molar teeth, which was ob- 

 tained by the Rev. J. Dennis from the Stonesfield-slate of Oxford- 

 shire, and named Stereognathus Ooliticus by Mr. E. Charlesworth. 

 This specimen, described in detail by Prof. Owen at the British As- 

 sociation Meeting in September last, indicated, in the author's opi- 

 nion, an animal allied to some extinct genera of even-toed Pachy- 

 derms, viz. the Hyracotherium, Microtherium, and Hyopotamus of the 

 Tertiary deposits ; and he concluded therefore that the Stereognathus 

 was most probably a diminutive non-ruminant Artiodactyle of omni- 

 vorous habits. 



With regard to the zoological reasons for referring this peculiar 

 and ancient fossil to the type of animal form above alluded to, the 

 Professor entered at some length into the analysis of the mental pro- 

 cesses by which the palteontologist aims at the restoration of an 

 unknown mammal from such a fragment as the fossil under notice. 

 Its mammalian character is decided by the two-fanged implantation 

 of the teeth, and its pachydermatous affinities are evidenced by the 

 peculiar sex-cuspid and cingulated molars. These zoological rela- 

 tions are determined from the knowledge that such structural pecu- 

 liarities obtain in certain known Pachydermata. Morphology, there- 

 fore, or the study of form, rather than physiology, or the known 

 relation of organs to function, is the guide in this determination ; 

 but the Professor expressed his opinion that this example could not 

 be cited as showing that there is no physiological, comprehensible, 

 or rational law (in contradistinction to the morphological or empiri- 

 cal) which can be a guide in the determination of fossil remains. 



