238 Sellards — New Tortoise and a Supplementary Note 



grooved between each tooth to receive the corresponding tooth 

 from the opposite jaw. Back of the tenth lower and eleventh 

 upper the teeth do not pass to the outer side of the jaw, but 

 are received in pits in the jaw. 



The symphysis of the jaw, as shown by specimens Nos. 

 6158 and 5879, begins opposite the eleventh or the twelfth 

 mandibular tooth. In specimen No. 5880, the front part of 

 which is wanting, may be seen sockets for seven teeth back of 

 the symphysis, representing apparently the eleventh to the 

 seventeenth or the twelfth to the eighteenth teeth inclusive, 

 from which it appears that the full number of teeth in the 

 lower jaw is seventeen or eighteen. The splenials, as noted 'in 

 the writer's original description, take part in the symphysis 

 and extend forward, as shown by the specimens now on hand, 

 to a point opposite the seventh mandibular tooth. The under 

 surface of the back part of the lower jaw is well shown by 

 specimen No. 5891 which is illustrated in the accompanying 

 text figure. The bones seen from the underside of the jaw 

 are the dentaries, splenials and angulars. The termination of 

 the dentaries is not definitely shown, but these bones may be 

 seen to extend approximately one half the length of the ramus 

 of the jaw. The limits of the splenials are very well shown 

 and are seen to extend somewhat more than one half the 

 length of the ramus. The angular is wedged in between the 

 splenials and the dentaries and forms the lower margin of the 

 jaw at the angle. 



While no one jaw has been found complete, yet an approxi- 

 mate measurement of the lower jaw may be obtained by com- 

 bining measurements from the two largest specimens of the 

 collection. In the larger of these, No. 6158, the front part of 

 the jaw as already noted is preserved, while in the other, No. 

 5891, which is but slightly smaller, the back part of the jaw is 

 practically complete. The symphysis of the jaw of the large 

 specimen measures 610 m,n , while on the slightly smaller speci- 

 men that part of the jaw back of the symphysis measures in a 

 direct line following the axis of the jaw 725 ,Iim . The full 

 length of the lower jaw of a large specimen of this gavial was, 

 therefore, somewhat more than 1335 mm , or about four feet and 

 three or four inches. By way of comparison it may be noted 

 that the splenial bones in this species take part in the forma- 

 tion of about four-elevenths of the symphysis ; while the sym- 

 physis itself includes about four-ninths of the entire length of 

 the jaw. The width of the jaw of the largest specimen, meas- 

 ured at the forward end of the splenial, is 170 mm , the jaw being 

 proportionately broader than that of the modern species of the 

 genus. 



A number of dermal plates of crocodillians are found at 

 this locality which with little doubt are referable to this spe- 



