NO. 1884. A NEW SPECIES, EDESTUS MIRUS—HAY. 33 



developed its portion of the shaft. The hinder end of the detached 

 portion of the shaft is irregular, as if some part had been eroded away. 



Figure 1 of plato 2 represents the riglit half of the block that 

 inclosed the specimen, while figure 2 presents a view of the teeth 

 that were exposed by digging tlirough from the underside of the 

 block. In figure 1 are seen impressions of the teeth of the lower 

 shaft and three of those (5, 6, 7) of the upper shaft. In the depression 

 which contained the lower shaft is seen a fragment, 2, of the latter, 

 which split off from the main portion. Behind and below this 

 depression is seen a large mass of calcified cartilage, which evidently 

 belonged to the lower jaw, including the symphysis. The upper and 

 anterior part of this, 8, forms a part of the bottom of the depression 

 mentioned and must have passed, partly at least, on the right-hand 

 side of the shaft, which would be the upper side on plate 1 . Below 

 and behuid this there is another mass, 9, which was probably in contact 

 with the left side of the shaft, but in the fossil does not quite reach 

 it (pi. 1) on account of some distortion or shoving before burial. 

 At 10, plate 2, is seen another part of the lower jaw. This ascended 

 to tlie pomt indicated by 7, as is shown by the impression on the 

 matrix. It overlay, that is, passed to the right of, the fragment of 

 the lower shaft and over the teeth 11 -and 12, wliich point forward 

 from the hinder edge of the block. What appears to be a continua- 

 tion of this cartilage is seen at 13, plate 1, passing under (to the left 

 of) the tooth 6. Tliis cartilage does not appear to be a part of that 

 which supports the two teeth 11 and 12, for there is a thin la^-er of 

 matrix between them. Nevertheless, it seems probable that these 

 teeth belonged to one of the jaws, upper or lower. Still another tooth 

 resembluig these and havmg its apex pointed m the same direction is 

 seen at 20, plate 2, figure 2. None of these tliree is attached to a 

 shaft, and they are straighter than are the teeth of the shafts. The 

 exposed surface of the bases of these teeth is rough and appears to 

 indicate that some part had been broken or eroded off. 



Returning to the lower jaw, it is to be observed that the symphysis 

 appears to have been at least 85 mm. long, occupying the full length 

 of the cartilage present. Since the lower shaft was developed along 

 this symphysis, the latter, as a bed for the former, might be expected 

 to be considerably elongated. 



Above the upper shaft is seen a mass of calcified cartilage, which 

 is regarded as havuig belonged to the snout and extending about as 

 far backward as the orbit. It is even possible that a part of the orbit 

 is included. Below the numeral 1^, plate 1, is a deep pit, which is 

 thought to be the nasal pit of the right side. It is surrounded by a 

 pavement of shagreen scales, each of wliich presents a central depres- 

 sion. There seems to be a chamiel rumimg forward from it to the 

 2044P— Proc . N . M . vol . 42—12 3 



