572 



PKOBOSCIDEA. 



rJ 





293 — X ppei molai 

 e enamel, 



ot Elepha<< ajncnnus 

 ' cement (from Owen). 



inenb., in the Pleistocene of Eur., As., and Ainer. The skin liad u thick 

 woolly covering, as is shown by the frozen carcases occasionally met 

 with in N. Siberia, where the tusks (sometimss from 10-12 feet in length) 

 are found in considerable numbers, affording ivory for export, and also by 

 contemporary drawings scratched on mammoth ivory. The cause 

 of the comparatively recent extinction of the mammoth is doubtful ; 

 it may have been due to the decay of the forests in which it liAed. E. meli- 

 tensis Falcon., a pigmy species fomid in caves in Malta. 



Extinct 

 crnera, Stego- 

 (ion Falc, 

 tu-^ksinupper 

 |cU\ , with en- 

 amel band ; 

 _iuiders com- 

 ])()^ed of 6-12 

 1 () w cusped 

 1 idges, with 

 cement i n the 

 ^• a 1 1 e y s , 

 Miocene and 

 Pliocene of Asia. Dinothermm Kaup, i x c g p J m f, the grinders 

 being bilophodont (except ml, which has 3 ridges), and all in f imction at 

 once, the premolars have milk predecessors ; the extremity of the mandible 

 is deflected and the tusks (lower incisors) project downwards (Fig. 295); 

 cranium depressed with but few air-cells : in size it surpassed living ele- 

 phants ; M. and U. Miocene of Eur. and As. Mastodon Cuv., i y^o 

 c fi p f m f ; u. incisors as large tusks with bands of enamel, 1. incisors 

 variable, never large, sometimes absent.; grinders with mammillated 

 ridges and scanty cement (Fig. 294), the anterior three gi'inders some- 

 times replaced, Miocene and Pliocene of Old World, in the New World 

 it survived until the 

 Pleistocene. Tetrahelodon 

 Cope, dentition, i \ c % 

 p f m I, the upper in- 

 cisors are tusks and the 

 lower are procumbent 

 teeth in close contact ; 

 there appear to have 

 been 3 deciduovis molars, 

 tlie last two of which 

 were replaced ; the pre- 

 molars were shed early ; 

 the premolars and molars 

 are brachyodont and bi- 

 or tri - lophodont, the 



ridges being tuberculated, and m'i has a tuberculated talon ; the sj'm- 

 physial region of the mandible is much elongated. Miocene and Pliocene 

 of Eur. Asia, Afr., N. Amer., extending into the Pleistocene in Amer. 



Palaeo mastodon Andrews, from the Upper Eocene of Fayum, Egypt ; 

 dentition i \ c "j p ^ m ^, the upper incisors are tusks, the lower pro- 

 cumbent and spatulate ; the premolars and molars very similar to those 

 of Tetrahelodon except that all were in use at once in the usual way, 



Fig. 294. —Oblique side and cro\\u Mew of the last 

 upper molar of Mastodon arvernensis (from Flower and 

 Lydekker). 



