178 



CHAPTEE XXVII. 



MULTUNGULA continued PROBOSCIDEA — EXTINCT ELEPHANTS — MASTODON — MAMMOTH, ETC. 



So far as can be gathered from their fossil remains, the Proboscideans entered on existence 

 at the earlier miocene epoch ; no particular form can be said to have taken precedence of the 

 rest, for in the oldest beds where their remains have been found, e^^dence of the existence of species 

 of the Mastodon and of the Elephant has alike been discovered. 



Mastodon (Maps 47, 48, and 49). — The Mastodon was an enormous Elephant-like animal with less 

 complex grinding teeth than the true Elephants, and with small projecting straight tusks in the lower 

 jaw in some (if not all the species), as well as with tusks, straight in some, curved in others, and 

 as large as those of the Elephant in the upper jaw. The projecting tusks in the lower jaw 

 remind us of those of the Ilii^popotamus, and still more of an enlarged typo of the Kangaroo 

 form of incisor in the Diprotodon. Nor is this resemblance limited to the tusks or incisors ; 

 it extends to the molars and other parts of the skeleton. Prof. Owen first referred the femur 

 of the Diprotodon to the Mastodon, and, in speaking of the molars observed, " The analogy 

 of the close mutual similarity which exists in the molar teeth of the Tapir, Dinothere, Manatee, 

 and Kangaroo, suggests the surmise, that the mastodontal type of molar teeth might also 

 have been repeated in a gigantic Marsupial genus, which has now become extinct ; and such 

 an idea naturally arose in my mind after having received evidence of the marsupial character 

 of the Diprotodon and Nototherium, two extinct Australian genera, with the tapiroid type of 

 molars represented by species as large as Rhinoceros."* 



The best characters for distinguishing the Mastodon from the Elephant are derived from the 

 teeth, which are more durable and more frequently met with than the other bones. The tusks in 

 the lower jaw, although not so uscfid for sectional characters as the molars, are perhaps the most 

 interesting and remarkable part of their structure. It was not until the year 1830, that any 

 susi^icion appears to have been entertained, that the Mastodons more than the Elephants possessed 

 tusks in the lower jaw, but early in that year a memoir by Dr. Godman was read to the American 

 Philosophic Society, upon a mastodontoid lower jaw with two small tusks, which he described as 

 characterizing a distinct proboscidean genus named by him Tetracaulodon. That name has 

 not been adopted, because it was afterwards found that this character belonged to all Mastodons, 

 or at any rate was as constant a character in them as the possession of tusks in the upper jaw is 

 in Elephants. In some Mastodons these tusks in the lower jaw are absent, and in others only 

 one is strongly developed ; but this appearance or absence is a sexual, an individual, or at most 

 a specific, and not a generic character. On its first discovery, however, it gave rise to much 



* "Annals Nat. Hist." xiv. p. 271, lSi4. 



