178 CATALOG OF FOSSIL FISHES IN THE MUSEUM 



E 2553 Fragmentary head of large individual, in counterpart, 

 showing mandible, maxilla, suborbital and the gular 

 plates. 



E 2554 Nearly complete fish so twisted as to show lateral view of 

 trunk and tail, and inner aspect of cranium; the sutures 

 of the cranium have opened so as to show the outlines 

 of the component plates. Body is somewhat macerated, 

 but the pectoral, ventral and caudal fins are preserved. 



E 2555 Side and top view of a crushed cranium, together with a 

 fragment of the pectoral fin. Roofing bones and jaws 

 well shown. 



E 2594 Pectoral region of large fish, showing squamation, and an 

 excellently preserved pectoral fin with its supports 

 (PL 70, fig. 2). 



Faniily ONYCHODONTID.E 



Genus Onychodus Newberry 



A genus of Crossopterygii known only by detached head plates, 

 jaw elements, teeth and scales. Its most remarkable feature is the 

 presymphyseal bone with its semicircle of teeth. Three American 

 species have been described, all from the Devonic; but of these two 

 seem to be synonymous — 0. sigmoides and 0. hopkinsi. The latter 

 was based on somewhat smaller and le&s curved teeth than 0. sig- 

 moides, but the materials now in various museums show that some 

 teeth from the hopkinsi locality are fully as large and as much curved 

 as any sigmoides teeth* 



Onychodus sigmoides Newberry^^ 



(PI. 58; text-fig. 59) 



Onychodus sigmoides Newberry, Proc. Nat. Inst., n. ser. i, 124, 1857. 

 Onychodus hopkinsi Newberry, Ibid., 124, 1857. 



This species is represented in the collection by a number of plates 

 and teeth. Of special interest are the remains from the Conodont 



8» For full synonymy see Hay, Bibliography and Catalog Fossil Vert. N. A., 1902, p. 363. 



