474 FAUNA ANTIQUA SIVALENSIS. 



British Museum. It is of an age intermediate between the sjDecimens 

 figured in Plate XXXV. 3, and Plate XL. 13. It is very valuable, 

 and is believed to be at present unique in Eiirope. (Reproduced in 

 Plate VIII. fig. 2.) 



Length of fragment of jaw, 1.5- in. Breadth, 4-3 in. Height, 4-1 in. Length of 

 first molar, 4' in. Breadth, 2'6 in. Length of second molar, 5'5 in. Breadth, 

 2-7 in. 



Fig. 16. — Mastodon Ohioticus. Fragment of upper jaw, with three 

 ridges and fangs of last upper molar, also empty cavity in jaw for fang 

 of fourth ridge. — B.M. 



Length, 6'1 in. Width, 4* in. Height of crown and fang, 7' in. 



Fig. 16 a. — M. Ohioticus. Last true molar, upper jaw, with four 

 main ridges and a heel ; the first ridge only very slightly touched by 

 wear. In Mastodon Ohioticus the upper teeth are distinctly cleft 

 lengthwise into two divisions, each division being indistinctly composed 

 of a pair of confluent points. The plane of the tooth is oblique, sloj^ing 

 trom the outside, Avhich is higher, to the inside, which is lower, and 

 this relation continues dui'ing the wear, the inside being the most worn. 

 The inner division, both anteriorly and posteriorly, throws off the 

 decurrent talon crests, but in the first two milk teeth the inner division 

 is smaller than the outer. Precisely the reverse is seen in lower jaw, 

 the inner ridge being the highest and remaining so during detrition, 



while the outer is the lowest but least complex B.M. 



Length, 7-3 in. Width, 4- in. 



Plate XLI. 



Tusks of Proboscidea.i Fragments and sections. 



Figs. 1 and 1 a. — Twisted fragment. — B.M. 



Length measured along great curvature, 40' in. Direct length or chord of cur- 

 vature, 28' in. Circumference at proximal end, 12'7 in. Circumference at distal 

 end, 13'2 in. 



Fig. 2.— B.M. 



Length, 56' in. Circumference at proximal end, 13'5 in. 



Figs. 3 and 3 a.— B.M. 



Length of fragment, 122 in. Circumference, 12'2in. Greatest diameter, 3-7 in. 

 Figs. 4, 4 a, and 4 J.— B.M. 



Length of fragment, 12-7 in. Greatest diameter, 7'7 in. Smallest diameter, 

 6' in. 



Fig. 5.— B.M. 



Greatest diameter, 98 in. Smallest diameter, 7"2in. 



Figs. 6 and 6 a. — Fragment of tusk in socket. 



Length of socket, 13'6in. Circumference of tusk, 6 '2 in. Breadth of incisive 

 alveolar margin, 6'2 in. 



Figs. 7 and 7 a.— B.M. 



Length, 68' in. Circumference at proximal end, 11 'in. 



Figs. 8 and 8 a.— -B.M. 



Length of fragment, 33- in. Circumference at smaller end, 16-5 in. 



' There is no evidence of any attempt the plate (with the exception of figs. 6 



made by Dr. Falconer to determine the and 25) are collected in one place in the 



species to which any of these specimens British Museum, 

 belonged. All the specimens figured in 



