1897. J NEW PALEOZOIC VERTEBRATA. 73 



These species are distributed as follows : 



Europe. N. America. 



H. nobilissimus. H. a77iericanus. 



H. giganteus. H. gtga?iteus. 



H. dewalkei. H. tuber cidatus, 



H. flemingii. H. radiatus. 



H. inflexus. H. hallii. 



H. leptopterus. H. serrulatus. 



H. paucidens, H. filosus. 



H. flabellatus. 



H. latiis. 



H. quebecensis. 



The H. nobilissimus, H. giganteus and H. flemingii are described 

 by Agassiz in the Poissons Fossiles. The H. tuberculatus, H. amtr- 

 icanus, H. radiatus, H. hallii and H. giganteus are described by 

 Newberry in The Paleozoic Fishes of N. America. The H. dewalkei, 

 H. inflexus and H. flemingii are described by Lohest in the Ann. 

 de la Soc. Geol. de Belgigue, t. xv, 1888. I described the H.fllosus 

 in the Proceeds. Amer. Philos. Soc, 1892, p. 228. I now give de- 

 scriptions of the H. serrulatus, i\\Q H. latus,^2in& the H. flabellatus. 



The Holoptychius seri^ulatus is based on a nearly perfect scale on 

 a piece of brown argillaceous sandstone, from Mansfield, Tioga 

 county. Pa., probably of Catskill age, although the color is rather 

 unusual. The scale is represented by a very clean cast, of which a 

 mould is figured in PI. II, Fig. 2. The species is one of the 

 large forms of the genus, the entire scale measuring about two 

 inches in vertical diameter. In characters this scale is of the H. 

 flemingii type, but the dimensions far exceed those of that species, 

 resembling in this respect the H. inflexus of Lohest. It differs 

 from that species in the more numerous, finer and less inosculating 

 ridges of the exposed part, and in the larger batch of tubercles con- 

 sisting of more numerous series, as pointed out in the analytical 

 table. The distal ridges become more prominent near the centre 

 of the scale, and terminate in some elevated portions which may be 

 cut off from the remainder of the ridges, one or two of them 

 becoming tubercles. The tubercles of the proximal part of the 

 scale are sharply defined cones, which increase in size as the series 

 radiate from the centre towards the proximal border of the scale. 

 The tract of tubercles extends over the entire base of the coarse 

 ridges, and not over a part of them only as in the H. inflexus and is 



