402 Bulletin American Museum of Natural History. [Vol. XIX, 



the crown as a whole is directed backward so as to make an 

 angle of 45° with the axis of the pedicel produced. As in 5. 

 atavus, the crown is flattened to anterior and posterior edges. 

 As in S. atavus, again, the teeth appear to graduate posteriorly 

 into the dermal scales; but this occurs at a greater distance 

 in front of the mouth than in the species from Sahel Alma. 



At 50 mm. in front of the mouth the rostrum is 46 mm. 

 wide; at a distance of 100 mm., 35 mm. wide; at the mouth, 

 75 mm. wide. The rostral cartilages have been well developed 

 and have left their impress on the matrix. These and all the 

 other cartilages present a mosaic of hexagonal calcifications. 

 From the point where these cartilages begin to narrow, in 

 front of the mouth, a band of stellate shagreen runs backward 

 along the sides of the head. In a few other places the sha- 

 green appears to have been circular in form and smooth. The 

 mouth resembles that of the living species of Pristis, and it has 

 a width of 50 mm. The teeth are small, and some of them 

 appear to have been furnished with one or more sharp ridges, 

 one of which was doubtless the cutting edge. 



The position of the gill arches is seen in the figure. On the 

 outer borders of each are seen the rays which supported the 

 gill septa. There can be no doubt that the gill slits opened 

 out on the lower side of the body, and that hence the genus 

 belongs to the Pristidae. 



This species is dedicated to Hiram, king of Tyre, the friend 

 of Solomon, who furnished for the latter cedar-trees and fir- 

 trees from the forests of Lebanon. 



Sclerorh5nichus sentus, sp. nov. 

 Plate XXVII, Figure i. 



The only portion of this fish that is known is a part of the 

 rostrum. This fragment, numbered 4504 (3864), has a total 

 length of 153 mm. The distal end of this rostrum is missing. 

 The proximal end of the specimen is supposed to have come 

 close to the mouth. From the distal end, where the width is 

 29 mm., the specimen expands gradually until, at a distance 

 of 80 mm. from the distal end, the width has become 45 mm. 



