1857.] FALCONER — MASTODON. 355 



different from the latter form. The remarkable sectorial tooth from 

 the Red Crag, which, according to Professor Owen, closely resembles 

 one of the ancient Carnivora called Hycenodon and Pterodon, and 

 which he suspects to be an indication of an extinct osculant genus, 

 linking on the true Felines to the Hysena or Musteline family, has 

 not been generically determined ; and it may have been washed in 

 from strata of the Eocene age * . 



If, on the other hand, a palfeontologist, having satisfied himself 

 that the Red Crag Mastodon is an undoubted Pliocene form, and 

 finding the same species in the Fluvio-marine Crag, were to infer that 

 they were both of the same geological age, and if he were then to 

 take a group of some of the well-established species as a starting- 

 point, he would experience little difficulty in reconciling many of 

 the more doubtful mammalian species with a consistent Pliocene 

 association. The species would run in the following order : — The 

 Proboscidea, M. (Tetralophodon) Arvei-nensis, E. {Loxodon) meri- 

 dionalis, and E. {Euelephas) antiquus ; the Pachydermata, Rhino- 

 ceros leptorhinus or Rhinoc. ?, Tapi?'usArvernensis, and Equus 



plicidens ; the Carnivora, Felis pardinensis, Ursus Arvernensis, and 

 probably a Pliocene species of Ca?iis. With such an harmonious 

 agreement in the great leading forms, he would naturally look to 

 Pliocene forms for comparison when he met with scanty and inde- 

 cisive remains of such a widely distributed and extensive genus as 

 Cervus, unless the characters were so pronounced as to be decisive of 

 species of an earlier age. 



This is the manner in which I have been led to regard the fossil 

 Mammalia of the Red and Fluvio-marine Crag ; and it has appeared 

 to me that (where remains obviously of an anterior epoch have not 

 been adventitiously intermixed) they agree generally, so far as the 

 species have been well determined, with the great Pliocene fauna of 

 Italy, as exhibited along the valleys of the Po and of the Arno. But 

 it must at the same time be freely admitted, that the materials upon 

 which the determination of many of the species of the Red Crag 

 Mammalia at present rests are so scanty and indecisive, that the 

 identification, either way, whether as Miocene or Pliocene forms, must 

 be regarded as little more than approximative. 



There are other considerations which corroborate the Pliocene 

 view of the Mammalian fauna of the Crag. The debateable species 

 referred by Prof. Owen to a Miocene origin all belong to genera that 

 are common to the Miocene and Pliocene periods — such as Mas- 

 todon, Rhinoceros, Tapirus, Sus, Cervus, and Felis. But of the more 

 remarkable types which are limited to the Upper Miocene deposits, 

 and which abound in them all over Europe, such as Dinofheriu?n, 

 Chalicotherium, Aceratherium, Anchitherium, Amphicyon, &c., not 

 a single remain has ever been cited as having been found in the 

 Crag-deposits. The question naturally arises, how does it happen, 



* Quarterly Journal of the Geol. Soc. vol. xii. p. 237. fig. 20. 

 VOL. XIII. — PART I. 2 C 



