88 THE TUSKS. 



The laminae at the anterior part of one of the tusks, which is best 

 preserved, are superficially not more than half a line in thickness ; they 

 are divided or split by longitudinal fissures, about three-fourths of an inch 

 apart ; they present none of the circular marks seen at the posterior extre- 

 mity. The point anteriorly is worn away for the space of two inches on 

 one side [vide Large Plate), as is generally found to occur in the tusks 

 of the Proboscidian family. 

 Direction. When the tusks were first discovered, they lay with their convexities 



outwards, their points approaching each other; having turned apparently 

 in their sockets after the soft parts, which retained them, were decomposed 

 so as to loosen their attachments (as represented in Vignette on title-page). 

 For the weight of the head inclined the butts downwards, while the resis- 

 tance of the marl on their inferior and internal sides would give a rotatory 

 motion outwards and upwards to a definite extent. In this direction they 

 were placed by Dr. Prime, who had an opportunity of observing them in 

 their original position in the imbedding marl. Although the extremities 

 of the butts are somewhat oval, the greater size of their sockets, owing 

 to the decomposition of the soft textures which lined them, would readily 

 admit the butts of the tusks to be placed in any direction ; and, considering 

 the apparent inutility and the remarkable anomaly of the position before 

 mentioned, we thought it right to change their .opposing aspect to one more 

 consonant with the character and attitude of the skeleton. 



The Inferior or Mandibular Tusk. — The small mandibular tusk has 

 been brought into notice of late years by Dr. Godman, who considered it as 

 characterizing a new species, to which he gave the name of Tetracaulodon, 

 as will be shown hereafter. Professor Owen has attached a new importance 

 to this tusk as one distinctive character between the genus Mastodon and 



