1892.] ^-J'-' [Cope. 



DIPNOI. 



Ganoehynchus oblongus, sp. nov. 



Established on what is either the symphyseal element of a mandible, or 

 a median bone of the superior mouth-arch. It consists of an oblong trough- 

 shaped plate with a thickened, somewhat revolute border, which is concave 

 in two directions ; that is, in the direction of the concavity of the trough, 

 and as a concavity of its free margin. This form indicates that it occupied 

 an oblique position, like the elements mentioned, so that the thickened 

 surface should fit closely the corresponding elements of the opposite jaw. 

 There is no enamel covering the masticatory border, but this may have 

 scaled olF. There are no lateral denticles as in the Holodus of Pander. 

 As compared with the O. beecherii of Newberry, this bone has the length 

 relatively much greater as compared with the width. The width in that 

 species exceeds the length several times, while in the O. oblongus the 

 width but slightly exceeds the length. The concavity of the masticating 

 border is greater ; the size is very much less. As compared with the G. 

 woodiiardii Traqu., this species is very much smaller ; there are no "na- 

 real " notches ; and no tubercles on the edge. 



The sides of the body of the bone are nearly parallel, and the posterior 

 border is gently convex. Two layers are visible ; the interior one, like 

 the external, has a coarsely punctate surface. 



MM. 



Lengthj^t '^"^^dle 9 



t-at border 10.5 



Width / ^^ proximal extremity 8 5 



<. at masticatory extremity 13.5 



From near Mansfield, Tioga county. Pa.; from the Catskill formation. 

 From Andrew Sherwin. 



TELEOSTOMATA. 



COCCOSTEUS MACROMUS, Sp. nov. 



Fragments of this species are abundant in the Chemung rocks at Leroy, 

 and I select as typical of it a pair ot supraclavicular and adjacent pieces, 

 which display its characters best. The supraclavicle has lost the condylar 

 articulation. Both extremities display the unsculptured surface, and the 

 usual groove extends obliquely across the sculptured portion at about two- 

 fiflhs the length from one of the extremities. The sculpture consists of 

 obtuse tubercles with delicate radiate-grooved bases, which are usually 

 separated by spaces equal to their own diameters, sometimes by narrower 

 spaces, but never by spaces which are wider. At some points they have 

 a linear arrangement. This sculpture is coarser than in the C. americanus 

 Newberry (see the Paleozoic Fishes of North America, by this author), 

 but resembles that of the C. decipiens Agass. of Scotland. From this 

 species the G. macromus differs in the elongate form of the supraclavicle, 



