AWARDS OF PREMIUMS. 69 



it is likely to become of mucli importance in settling the history 

 of that extinct animal. It is now deposited in the collection of 

 Dr. John C. Warren, of Boston, Massachusetts. 



At a meeting of the Boston Society of Natural History, held 

 in January, 1855, the following communication was received 

 and read, from Mr, I. A. Lapham, of Milwaukee, Wisconsin : 



'• On the number of teeth of the Mastodon Giganteus." 



'* Much interest was imparted to the Annual Exhibition of the 

 Wisconsin State Agricultural Society for 1854, by a fragment 

 of the lower jaw-bone of the extinct Mastodon giganteus, found 

 buried six feet deep in the ground, at a place known as Terre 

 Coupee, Michigan, by M. H. Taylor. It was the right ramus, 

 and a small portion of the extremity of the left, with three teeth, 

 the anterior one much worn, especially on the exterior side. 

 Its entire length is 26 inches; its height and thickness is 6 1-2 

 inches, measured opposite the space between the last two teeth. 

 The posterior elevated portions of the jaw are broken off, and 

 also the pointed extremity, where no traces are to be seen of 

 the small tusks that belong here, or of their cavities. 



The anterior tooth consists of six mastoid processes, forming 

 three transverse ridges, interrupted by a central depression ; but 

 the three inner processes are worn off obliquely, and the outer 

 half of the tooth is worn down to the base of the eminences. 

 Where the enamel is worn off, the dentine or bony matter with- 

 in, constituting the main body of the tooth, is covered with a 

 black, very hard, horny layer. The hardness of this thin coat- 

 ing aids the mastication of food, and materially retards detrition. 

 There are two fangs, but the posterior one appears to be made 

 by the union of two. The tooth is loose, easily removed from 

 its place, and the extremities of the fangs are much abraded. 

 The bone appears to be filling the socket from below, so that 

 the tooth is clearly deciduous, and would soon have been shed. 



The next and middle tooth is the largest and most prominent 

 of the three. It has four ridges or eight cusps, and the rudiment 

 of another ridge o:i the posterior end. The three inner cusps 

 are most worn, the anterior inner one having entirely disappeared. 

 This tooth is pressed closely against the anterior tooth, as if 



