DEVONIC FISHES OF THE NEW YORK FORMATIONS 8 1 



Apateacanthus vetustus (Clarke) 



Plate 3, figure 5 



1885 Pristacanthusvetustus J. M. Clarke. U. S. Geol. Sur. Bui. 16, p. 42, 



pi. I, fig. 7 

 1889 Pristacanthus vetustus _/. S. Newberry. U. S. Geol. Sur. Monogr. 



16:61 

 1891 Apateacanthus vetustus A. S. Woodward. Cat. Foss. Fishes Brit. Mus. 



pt 2, p. 119 



Known 'Only by the type specimen, which is extremely imperfect, but 

 presents characters suggestive of Chimaeroid affinities. Spine composed of 

 an extremely thin layer of vasodentine, probably hollow internally, lateral 

 surface nearly flat, of uncertain width, without costae, and covered with 

 sparsely scattered stellate tubercles of extremely minute, almost microscopic 

 size. Posterior border set with closely spaced hook-shaped denticles of 

 relatively large size, their apexes directed downwards. 



It is unfortunate that the .specimen which affords the only information 

 we possess of this genus and species should have been considerably injured 

 in fossilization, both extremities being broken away, and also a part of the 

 sides, including the whole of the anterior margin. The width, therefore, of 

 the lateral surface, as well as the total length of the spine, is indeterminate. 

 However, the preserved portion indicates a spine of large size, gradually 

 tapering, and perhaps slightly arcuate in form. In two respects the spine 

 may be said to be quite remarkable ; first, for the large size and close 

 approximation of the posterior denticles, 14 of which remain intact ; and 

 secondly, for the rudimentary nature of the ornamentation. The tubercles, 

 still faintly stellate, are almost imperceptible to the unaided vision, and are 

 without regular arrangement. The flat sides, tuberculated ornament, and 

 absence of longitudinal costae are characters which suggest affinity with the 

 two preceding genera, hence the form may be looked upon as a late sur- 

 vival of Mesodevonic Chimaeroids. The type specimen is preserved in the 

 United States National Museum. 



Formation and locality. Upper portion of the Cashaqua shale (Port- 

 age) ; near Milo, Yates county, N. Y. 



