BY J. DOUGLAS OGILBY. 423 



and entire,* the remainder of the cusp being swollen and the tip 

 obtusely pointed; the external portion is broader than the inner 

 and is more or less truncated; it is as long as or shorter than the 

 inner portion; mandibular plate with ten cusjds, the outer one on 

 each side acute and directed inwards and backwards, the other 

 short and blunt, sometimes rudimentary ; the inner seines of 

 discal teeth are enlarged, triangular and acute in front, broad 

 and chiselled on the sides, those behind the mandibular plate 

 growing gradually smaller towards the middle; these teeth are 

 twenty-eight in number and the anterior pair correspond to the 

 inner maxillary cusps; in front of the interspace between the 

 anterior pair is a series of six teeth, which gradually decrease in 

 size from within and extend in a straight line to the rim of the 

 disk; from these and from the enlarged circumgular teeth extend 

 curved series of graduated teeth; these series are widely separated 

 from one another and the teeth themselves are not in contact 

 basally; there are no small teeth behind the jDostmandibular 

 series; the tongue is armed with a single pair of dorso-lateral 

 plates, each of which is deeply grooved near its outer border, 

 which is strongly convex, blunt, and entire, while the inner 

 border is quadricuspid, the anterior cusp being only about half 

 the length of the other three, which are subequal in size; the 

 transverse, ventribasal plate is also grooved round the base of the 

 cusps, but is otherwise smooth ; the cusps are two in number, 

 long, acute, and directed outwards and slightly upwards; there is 

 a minute median basal cusp behind the plane of the functional 

 pair. The vent is situated beneath the origin of the second 

 dorsal; the length of the tail is 5J to 64 in the total length. The 

 distance between the origin of the first dorsal fin and the tip of 

 the tail is 2 to 2^ in its distance from the extremity of the snout; 

 both dorsal fins rise gradually from the dorsal integument in 



* Giinther describes the outer cusps in (/. aUporti as being "finely 

 serrated on the inner margin," but there is no trace of any sucli serrature 

 in either of my specimens, though they agree perfectly in tlie transversely 

 plicated bod}'. 



