POM ATOM IDuE LOPHAR 45 



other from the insertion ; a single spine of the dorsal present, this joined 

 by a membrane to the soft rays (the rest obliterated). No traces of 

 finlets, armed lateral line or barbels. 



Ventral fin with its spine beneath the third vertebra, the pectoral 

 beneath the fourth and fifth. The ventral has one spine and five soft 

 rays, the spine being short and strong; shorter than the pectoral. 



Dorsal fin D. I, 20, with one evident spine of medium strength, 

 opposite the fourteenth vertebra. Presumably the other spines have 

 been lost, as interneural impressions begin opposite the seventh vertebra 

 and doubtful traces of an external fin here are shown. Base of soft dorsal 

 slightly longer than anal and very similar to it. In both the anterior 

 rays are moderately elevated; the other rays decrease rapidly backward. 

 Dorsal spine is half the length of snout and three-fourths the orbit. 



Pectoral fin entire, acutely pointed, the upper rays quite long, lower 

 quite short, the middle of the base rather low. 



Anal fin (II) I, 28, slightly shorter than the dorsal, its posterior 

 elements very weak. The single stout spine present seems joined by 

 membrane to the soft rays. There are three interhaemals for spines 

 plainly visible, the middle one of which is the strongest, suggesting the 

 probability of three spines in the original fish, as in the living Blue-fish. 



Caudal fin of thirty-four rays, is deeply forked with a hypural divided, 

 with a long diamond-shaped space between. Each part supports nine 

 strong rays and eight short weak rays on either side, supported also by 

 the last vertebra; the stronger support is given to the upper rays. 



Preopercle apparently finely serrate, ending in a single, blunt, flat- 

 tened point, in front of which it is broadly rounded. 



Lower jaw projecting, set with decidedly stout conical teeth of 

 moderate length, in definite sockets, and comparatively uniform in 

 size. Each tooth is slightly appressed, feebly curved inward and back- 

 ward, armed with a smooth cutting edge fore and aft, the posterior 

 edge being the more sharply so; some small teeth are found among the 

 larger ones and not all seem to be in the same direct row. No distinct 

 canines are found, and teeth are shown only on the premaxillaries and 

 dentaries, the other bones not being visible. The articulation of the 

 mandible occurs just before the front of the eye. 



Eye large, set midway in head. 



Scales ctenoid, judging, however, by only one incomplete scale. It 

 has eleven or twelve coarse radiating ridges crossed near the margin by 

 very fine concentric striae. The distribution cannot be determined, since 

 nearly all are lost. The scale occurs in the matrix near the caudal fin. 



Vertebras, 1 1 + 14 = 25 in number, decreasing slightly from the 

 fourth forward ; caudals from the twentieth backward diminishing to the 



