448 Mr. G. A. Boulenger on 



is due, I think, to injury of tlie specimen and not to a specific 

 difference, the " ddchirure du bord dorsal du tronc en arri^re 

 de cette nageoire," to which the author alludes, and which is 

 shown in the figure, accounting for the absence of the poste- 

 rior half of the fin. 



The anal fin is triangular, much deeper than long, and 

 fulcrate like the dorsal ; its base measures nearly half that of 

 the dorsal. I count about 20 rays. 



The pectoral fin has been described by Van Beneden as 



" comparativement peu developpde, arrondie et non 



pas anguleuse " ; and Traquair believed it to have been small, 

 recognizing, however, its imperfect preservation. It is, on 

 the contrary, long, longer than as restored by Fraipont, wlio 

 made a much better guess at its real shape, nearly as long as 

 the head, falciform, very similar to and but little smaller than 

 that of Eurynotus. Its base is covered by 4 scales, the outer 

 of which is much elongate and continued as a series of fulcra 

 along the edge of the fin. The whole pectoral arch is well 

 seen in specimen B, from which fig. 1, PI. X.,is taken. The 

 post -clavicle overlapped the outer surface of the clavicle; 

 the same is the casein Chondrosteous Ganoids and Clupeidas 

 alone among recent fishes, the post-clavicle being almost 

 universally applied to the inner surface of the clavicle. 



The ventral fin has a rather elongate base and, I think, 

 13 rays. 



The caudal fin has been incorrectly represented in the type 

 specimen owing to its imperfection. This accounts for 

 Van Beneden's curious statement : " Le lobe inferieur ne 

 parait gtre qu'une seconde nageoire anale." For, as in the 

 specimen studied by Fraipont, the rays really extend along 

 the lower border of the prolonged axis, clad with small 

 lozenge-shaped scales, almost to its extremity, as in Palceo- 

 niscus, Eurynotus, and allied forms. The large ridge-scutes 

 which reappear behind the dorsal and anal fins are continued 

 as a series of fulcra along the upper and lower lobes of the 

 caudal fin ; but it still remains undecided whether their 

 arrangement was monostichous or distichous. 



The scales, strongly imbricate and with the usual peg-and- 

 socket articulation, number 63 in a longitudinal series and 35 

 in an oblique transverse series ; they are, like the doi'sal ridge- 

 scutes, finely striated, a striation I w ould describe as pro- 

 duced by grooves rather than by raised ridges. The scales 

 on the middle of the side are tetragonal, twice to twice and a 

 half as deep as broad, considering only the exposed surface, 

 obliquely striated, the striation being more distinct on the 

 anterior half of the body than further back. As usual, the 



