118 PALEOZOIC FISHES OF NORTH AMERICA. 
inferred that they were possessed by Glyptopomus. Should it prove, how- 
ever, that they are absent in this genus, we should be compelled to give to 
our fish a new generic name, and I would call it Glyptognathus, in allusion 
to the conspicuous ornamentation of the mandibles; distinguishing it from 
Glyptopomus by its lateral jugulars, from Glyptoliemus by the absence of 
pectoral plates. To avoid, however, the possible multiplication of syno- 
nyms, already sufficiently numerous, I have thought it better to unite it 
with Glyptopomus until the question of the presence or absence of lateral 
jugular plates in that genus shall be decided by the discovery of more 
material. 
The triangular accessory jugulars in Glyptopomus minor might be con- 
sidered as evidence of generic distinctness from our fish, but until they 
shall be found in other individuals or other species they cannot be proven 
to be other than individual or specific characters. 
The specimen described above remains up to the present time unique; 
and yet on the slab on which it lies are portions of two other individuals 
which, like it, were probably preserved entire. I have made much effort 
to obtain other specimens; hitherto without success. There is very little 
doubt, however, that the Catskill rocks will hereafter yield more remains 
of this fish,.as well as of others of which we have up to the present time 
only very imperfect representation. 
Dirtrerus (Crenopus) Suerwoop!, Newb. 
Plate XXVII, Figs. 3-3». 
Dipterus Sherwoodi, N.; Paleontology of Ohio, vol. 2, pl. 58, fig. 17. 
Teeth one inch in length, triangular in outline; crown marked with 
three prominent tuberculated ridges, separated by deep furrows somewhat 
wider than the ridges. The strongest of these ridges forms one side of the 
triangular tooth. On the angle opposite this side are a few irregular tuber- 
cles, but no traces of distinct ridges. The denticles which crown the ridges 
are somewhat compressed laterally, are rounded, smooth, and blunt at the 
summit. 
This is apparently one of the upper palate teeth of a species of Dipterus, 
and is specially interesting as being the first relic of the genus found on 
