190 Description of new Palaeozoic Fishes. 



jugular plates, bordered by five lateral jugulars, of which the anterior is 

 linear, hut broadest behind; the middle three are rhomboidal; and the pos~ 

 terior is spatulate and the largest of the series. Pectoral fins elliptical in 

 outline, deeply lobed and scaled. Scales rhomboidal or quadrangular* 

 smooth beneath, strongly marked on the outer surface with short curved 

 vermicular furrows, divided by sinuous ridges. 



Until the upper surface of the head of this lish can be found 

 displayed, it cannot be asserted that it belongs to the genus 

 Glyptopomus / and even with entire correspondence in the 

 cranial bones, its jugular plates may be different; for it is not 

 yet certain that Glyptopomus had lateral jugulars. The 

 scales are, however, precisely those of Glyptopomus, and it 

 wants the pectoral plates of Glyptolemus, although its lateral 

 jugulars are similar. It has also more the general aspect of 

 Glyptopomus, and it is therefore placed provisionally in that 

 genus. Up to the present time, no other specimen of this 

 fish has been found than that now described, and this is of 

 special interest as indicating the former existence in America 

 of another fish closely allied to those of the Upper Old Red 

 Sandstone of Scotland. 



'From the Catskill Group, Wyoming Co., Perm. 



Specimen presented by Mr. Sayre to the cabinet of Lehigh 



University, Bethlehem, Penn. 



Archseotaatis- Nov. G-en. • 



Dentition flat and pavenient-like ; teeth of large size, thick and massive, in 

 several rows, the different series arched and increasing in size from behind 

 forward ; under surfaces somewhat excavated to fit the curvature of the car- 

 tilaginous jaw ; upper third of teeth formed by a coat of enamel, transversely 

 corrugated and punctate. 



The teeth on which the above description is based have the 

 general form of those of Psammodus, but they are many times 

 larger, and are distinguishable from them by the beautifully 

 regular transverse corrugation of the enameled surface, like 

 that of the teeth of Rhina. A number of teeth, found in jux- 

 taposition, show that the dentition was much like that of the 

 living rays, especially MyliooaMs ; and there can be little 



