32 PROCEEDINGS OF THBf NATIONAL MUSEUM. vol. 42. 



The remains consist, as interpreted, of two tooth shafts, one belong- 

 ing to the upper jaw, the other to the lower; a part of the lower jaw, 

 and the anterior end of the cranium. There seem to be few or no 

 remains that represent the upper jaws or palato-quadrate arch. As 

 is too often the case, the absence of parts that might have been 

 secured is to be regretted. On the left of the block of shale, as repre- 

 sented in plate 1, the cranimn extends to the edge, and there is no 

 doubt that it continued into the block adjacent. Probably near by, 

 in other directions, there were scattered portions of the skull. Of 

 less importance is the fact that the apices of some of the teeth were 

 lost after the block was split. 



The parts, except the teeth and the shafts bearing them, are com- 

 posed of calcified cartilage. The natural surface of most of this ap- 

 pears to be somewhat regularly pitted, and this pitting is beheved 

 to be due to the presence of shagreen scales, each of w^liich seems to 

 have had a central depression. The shaft that belonged to the upper 

 jaw has a greater diameter than that pertaining to the lower jaw. It 

 is also longer and not so strongly curved. The upper shaft has a 

 length of about 185 mm., but a portion is missing from the front 

 and possibly a fragment is gone from the hinder end. The diameter 

 about the middle of the length is 32 mm. The lower shaft has a 

 length of about 150 mm. The diameter is 26 mm. In the upper 

 shaft six teeth are distinguishable, but one is missing from the front 

 end, while two others are seen in section on the left-hand edge of the 

 block (pi. 1, 16, 17), but do not show in the figure. 



The teeth have a height of about 28 mm., in a straight line from the 

 apex to the middle of the base. One margin, the anterior, is convex, 

 the other concave. Each margin possesses about 25 denticulations, 

 those of the anterior border being slightly larger. Most of the 

 denticulations are simple, but a few of them have one or more 

 notches near the summit. The hinder part of the lower shaft (pi. 1,3), 

 including two teeth, had, at the time of burial, suffered dislocation. 

 One of these teeth is seen at 4- (pl- 1 and pi. 2, fig. 2) ; the other 

 lies under the fifth tooth of the upper shaft and was found by digging 

 through the block from the other side (pl. 2, fig. 2, 18). It is evident 

 that the hinder segments of the shaft had not yet become thoroughly 

 consolidated and that maceration and a sUght disturbance had led 

 some displacement. On the upper border of the shaft, behind the 

 fifth tooth, is a groove into which the base of the displaced sixth 

 tooth had fitted. Counting the two displaced teeth, there would be 

 seven in the lower shaft. However, in the excavation made from 

 the underside of the block, there is seen a tooth (pl. 2, fig. 2, 19) that 

 is free from any part of a shaft. It appears possible that this tooth 

 belonged behind the one indicated by the^ numeral 4 and had not yet 



