412 E. S. GOODRICH. 



character of these remains, Blainville was opposed in Paris by 

 Dumeril (9) and Geoffrey Saint-Hilaire (27), whilst in Eng- 

 land he was supported by Professor Grant (11) and by Ogilby. 

 The latter took up a more impartial position, and considered that 

 they were not justified by the evidence in pronouncing whether 

 the fossils were mammalian or reptilian, arguing in favour of 

 saurian affinities that the molars and premolars could not be 

 distinguished, that the canine and incisors occupy five twelfths 

 of the dental line, that the incisors (in the type Phascolothe- 

 rium) are nearly in the same straight line as the grinders, and 

 that the condyle is below the level of the crown of the teeth (13). 

 On returning to England, Buckland entrusted to Owen 

 these " bones of contention," as the latter calls them, for the 

 purpose of making an exhaustive study to ascertain their true 

 nature. In 1838 Owen read two papers on this subject before 

 the Geological Society (18), and in 1842 his full treatise was 

 published with carefully executed figures (19). Owen drew 

 attention to such Mammalian characters as the convex articular 

 condyle, the broad, high, and curved coronoid process, situated 

 immediately in front of the condyle and resembling that of 

 the opossum, and the separate angle inflected as in Marsupials 

 and some Insectivora. He then described the teeth in detail, 

 comparing the six molars of Amphitherium to those of Didel- 

 phys, and the four premolars to those of Didelphys and Talpa. 

 For the first time Owen definitely pointed out that the molars 

 of these animals closely resemble each other, belonging to the 

 type of tooth now known as the tritubercular-sectorial. " An 

 interesting result of this examination is the observation that 

 the five cusps of the tuberculate molares [of Amphitherium] 

 are not arranged, as had been supposed, in the same line, but 

 in two pairs placed transversely to the axis of the jaw, with the 

 fifth cusp anterior, exactly as in Didelphys, and totally different 

 from the structure of the molares in any of the Phocse, to which 

 these very small Mammalia have been compared" (18). It is 

 surprising, after this, to see Professor Osborn, fifty years later, 

 claiming the " discovery " of tritubercular molars in Amphi- 

 therium (16). 



