PALAEONTOLOGY 



possessing one lower tusk from Waldringfield and a second from Wood- 

 bridge, while the Ipswich Museum has an incisor. Cheek-teeth from 

 the Crag indicate the occurrence of two species of wild pig — a larger 

 and a smaller. The larger may be identical with one of the two con- 

 tinental Pliocene forms described as Sus antiquus and S. erymanthius, while 

 the smaller may be the same as S. palceochcerus of the German Pliocene. 



Of the horses (or perhaps asses or zebras) remains are rare in the 

 Crag, but there is one tooth of an Equus from the Red Crag of Bawdsey 

 in the British Museum, and a second from Felixstow in the York 

 Museum. Less uncommon are cheek-teeth of the three-toed horses of 

 the genus Hipparion, which can be readily distinguished from those of 

 Equus by the pattern on the grinding surface. All the known speci- 

 mens of these teeth appear to come from the Red Crag nodule bed ; 

 the species to which they belong is probably the widely spread H. gracilis 

 of the continental Pliocene. 



Cheek-teeth of rhinoceroses, often broken, are not uncommonly 

 met with in the Red Crag nodule bed of the county, most of which it 

 was once thought might belong to some of the Pleistocene representa- 

 tives of the genus. They may however with more probability be as- 

 signed to continental Pliocene types, such as the hornless Rhinoceros 

 incisivus and the two-horned K. schleiermacheri of Germany. Tapirs, 

 too, are represented in the Red Crag nodule bed of the county by their 

 teeth, and are perhaps specifically identical with the continental forms 

 described as Tapirus arvernensis and T. priscus. The occurrence of these 

 fossil European tapirs, it may be incidentally remarked, is a fact of con- 

 siderable interest, since they serve to connect the present widely separated 

 habitats — Malaya and tropical America — of this primitive group of odd- 

 toed ungulates. 



With the exception of the recently discovered Pliocene cave near 

 Buxton, the Crags of Norfolk and Suffolk are the only deposits in Britain 

 from which are obtained the teeth of those primitive elephants known 

 as mastodons. In these mastodons the cheek-teeth, or molars, are of a 

 much more simple structure than those of the true elephants, being in 

 fact in many respects more like those of gigantic pigs than of the latter. 

 In place of consisting of a great number of closely packed tall parallel 

 plates, the crowns of the molars of the mastodons are formed by a 

 few low columns or ridges, with open valleys between them. Some 

 mastodons have three ridges or rows of columns in each molar save 

 the two front pairs and the last, but in others the number of ridges is 

 four in the teeth in question. Many of the Crag mastodons belong to 

 the species with four-ridged molars originally described from the Auvergne 

 under the name of Mastodon arvernensis, and characterized by the alter- 

 nating arrangement of the cusps on the crowns of those teeth and the 

 slight prolongation of the front of the lower jaw. Other teeth from 

 the Red Crag belong to a second four-ridged species, the continental 

 M. longirostris. One particular molar, with three ridges, from the Red 

 Crag nodule bed near Woodbridge, now preserved in the York Museum, 



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