On Tetracaulodon (Tetrabeloclon) Shepardii, 



Cope. 



BY GEORGE WAGNER. 



With Plates XXIV, XXV. 



In the paleontological museum of the Universit}' of Kansas is the 

 mandible of a mastodon, from the Loup Fork beds of Phillips 

 county, Kansas. It consists of a nearly complete left ramus, with 

 the last molar in place. (See Plate XXIV). The jaw agrees so com- 

 pletely with Tetrabelodo7i sJicpardii, described by Cope*, that it must 

 be considered as belonging to that species. The jaw is very well 

 preserved. The tusk is not present, but its alveolus is plainl}- 

 seen, and indicates a tusk slanting downward at quite a steep angle. 

 The symphysis is short and abruptly descending. 



The last molar has four crests and quite a prominent keel, the 

 internal half of each crest is slightly in advance, the outer lialves of 

 the first three crests are worn into trefoils. The tooth tapers very 

 slightly to the rear; there is but little cement in the valleys; the 

 cingulum is prominent. 



In front of this molar the alveolus is empty. The fore part of 

 the ramus is elevated, descending steeply to the symphysis. Below 

 this elevation, about one-fourth the way down the side, is the men- 

 tal foramen, lo mm in diameter. The curve between the coronoid 

 and condyloid process ascends gradually, and is not deeply notched, 

 as is the case in Mastodon Amcricaniis. 



Measurements: 



Length of ramus and symphysis 565 mm 



Length of ramus to symphysis 475 " 



Depth of ramus, posterior end of. last molar 130 " 



Depth of ramus, anterior end of last molar 120 " 



Depth of ramus, at elevation 165 " 



Width of ramus, posterior end of last molar 112 " 



Width of ramus, anterior end of last molar go " 



Diameter of last molar, anterior, posterior 180 " 



*A Preliminary Report on the Vertebrate Paleontology of the Llano Estacado, p. 57. 

 (From Fourth Annual Report, Geological Survey of Texas.) 



(99) KAN. UNIV. QUAR,, VOL. VIII, NO. 3. APR., 1899, SERIES A. 



