193 

 PIMELODUS. 



PlMELODUS ANTIQUUS. 



•Among the fossil-fish lemains of Professor Hay den's collection from the 

 junction of the Big Sandy and Green Rivers, there are a number of fragments 

 of pectoral spines and a few jaw-fragments of a species of cat-fish. 



The pectoral spines, of which two fragments are represented in Figs. 44, 

 45, Plate XXXII, are like those of our living cat-fish. A fragment compris- 

 ing about two-thirds of the symphysial portion of a dentary bone, -Fig. 46, re- 

 sembles the same in the recent cat-fish, and, as in it, was covered with a broad 

 card-like surface of teeth. The breadth of the dentary surface near the sym- 

 physis is 3£ lines. The pectoral spines have ranged from an inch to upward 

 of 2 inches in length. The size of the specie was from afoot to 18 inches. 



PHAREODUS. 



Phaeeodus acutus. 



Accompanying the remains of gars and cat-fish, from the junction of the 

 Big Sandy and Green Rivers, there are many fragments of jaw-bones and 

 others with teeth, evidently not belonging to either of those genera of fishes. 

 They also present sufficient peculiarity to render it probable that they may 

 not belong in the same family with Amia, and therefore probably not to the 

 closely allied genera supposed to be indicated by the vertebral specimens 

 described in the preceding pages. The means of comparison at my command 

 are too scanty to enable me to determine the affinities of the fish to which 

 the fossils pertain. 



Figs. 49, 50, Plate XXXII represent two of the best preserved and more 

 characteristic of the specimens, consisting of fragments of dentary bones. 

 These, are proportionately deeper and stronger than in Amia. They support 

 a single row of long teeth at the border, and possess no patch of smaller 

 teeth internally such as exist in Amia. . The teeth are cylindro-conical, with 

 their somewhat thickened bases close together and firmly co-ossified with the 

 jaw. Their shaft is straight and not curved as in Amia, but the sharp coni- 

 cal apex is bent inwardly. • 



Figs. 47, 48 represent fragments of premaxillaries. In these the teeth 

 are of the same character as in the dentary bones, but are less bent at the 

 tips. 



25 g 



