E'OSSIL MAMMALIA FROM THE STONESFIELD SLATE. 409 



that these bones belonged to any of them, 1 need only men- 

 tion that Seeley considers that they are " limb bones indicating 

 a generalised insectivorous type, modified from a Monotreme 

 stock in the direction of the Marsupial plan." 



Genus Amphitherium. 



Four of the fossil jaws appear to belong to this genus. Three 

 of these, two of which are type specimens, are in the Oxford 

 Museum; the fourth is in the British Museum. 



Amphitherium Prevostii, Blainville. 

 Type specimen, P). 26, fig. 1. 



A left ramus of the lower jaw, seen from the inside; in the 

 Oxford Museum. 



In 1824 ^ Dr. W. Buckland, the well-known geologist, first 

 announced the discovery of the remains of mesozoic Mam- 

 malia in his paper ' on Megalosaurus ' (5). He there mentions 

 " two portions of the jaw of the didelphys or opossum," which 

 he refers " to this family on the authority of M. Cuvier, who 

 has examined it." From Mr. W. J. Broderip we learn that 

 these rare fossils were obtained as follows : — " An ancient 

 stonemason living at Heddington . . . made his appear- 

 ance in my rooms at Oxford with two specimens of the lower 

 jaws of mammiferous animals, embedded in Stonesfield slate. 

 . . . One of the jaws was purchased by my friend Professor 

 Buckland, who exclaimed against my retaining both" (4). 

 The fossil purchased by Broderip himself is the type specimen 

 of Phascolotheriura (see below) ; Buckland's fossil is the type 

 specimen with which we are now concerned. He placed it in 

 the Ashmolean Museum, whence it has come with the other 

 specimens of the Buckland collection to its present home, the 

 Oxford University Museum. The exact date at which it was 

 purchased I have been unable to ascertain for certain ; it was 

 probably about 1814: the date given by Zittel is 1812 (32), 

 but I know not on what authority. 



Cuvier, who visited Oxford in 1818, says of these fossils 

 ^ Not 1823, as is generally stated to be the case. 



