410 MEMOIRS OF THE CARNEGIE MUSEUM. 



26. Gyrodus macrophthalmus Agassiz. (Plate LXIX, fig. 1.) 

 (For synonymy cf. A. S. Woodward, Cat. Foss. Fishes Brit. Mus., Pt. Ill, p. 233.) 

 This species is represented in the collections of the Carnegie Museum by a 

 well-preserved individual having a total length of 25 cm. (No. 4734) showing the 

 characteristic scale-markings and part of the dentition. Hennig's proposal to 

 suppress this, the type-species, and also G. frontatus, in favor of Blainville's term, 

 G. hexagonus, cannot be sustained. 



27. Gyrodus frontatus Agassiz. (Plate LXI, fig. 3.) 



(For synonymy cf. A. S. Woodward, Cat. Foss. Fishes Brit. Mus., Pt. Ill, pp. 

 235-6.) 



A species, so far as known, closely similar to the type, only differing in the 

 relatively greater protuberance of the abdominal region, in the simple mammillation 

 of the teeth, and in having the tubercular ornamentation of the scales without 

 reticulations, extending over the ventral half of the fish {cf. A. S. Woodward, I. c, 

 Pt. Ill, p. 236). 



This form is well represented in the collections of the Carnegie Museum, 

 the examples belonging to it being cataloged as follows: 10, 690, 691, 3003,4685, 

 4735 (in counterpart), 4736, 4763 (in counterpart), 4796, 4797 (in counterpart), 

 4798 (in counterpart) , 4799, 4893. The figure on PL LXI is unfortunately reversed. 



28. Gyrodus circularis Agassiz. (Plate LXIX, fig. 2.) 

 (For synonymy cf. A. S. Woodward, Cat. Foss. Fishes Brit. Mus., Pt. Ill, p. 238.) 

 A magnificent example of this species, having a total length of 75 cm., forms 

 one of the most attractive exhibits of fossil fishes to be seen in the Hall of Vertebrate 

 Paleontology in the Carnegie Museum. It is cataloged as 4407x. Another 

 specimen (Catalog Number 4407), of even larger size shows the well-preserved 

 squamation of the left side of the trunk. 



Family EUGNATHID^. 



Genus Eugnathus Agassiz. 



29. Eugnathus longiserratus (Agassiz). (Plate LXIV, figs. 1 and 2.) 



(For synonymy cf. A. S. Woodward, Cat. Foss. Fishes Brit. Mus., Pt. Ill, p. 301.) 



Three well-preserved specimens referable to this species form part of the 



exhibition series of the Carnegie Museum, and are cataloged under the numbers 



4686, 4719 (in counterpart), and 5021 respectively. 



