SOME NEW DEVON IC FOSSILS 199 



Pterinopecten denysi nov. 



Shell moderately large, subcircular, known only from its left 

 valve which in the single specimen before lis is somewhat incom- 

 plete about the hinge but has a very characteristic sculpture. This 

 consists primarily of a few strong radial ribs of unequal size, which 

 rapidly spread apart leaving broad interspaces which do not. in 

 any noticeable degree on the body of the shell, become occupied 

 by other ribs, except small and simple ones of a secondary series. 



Pterinopecten denysi 



The primary ribs themselves widen, become broad and flat and 

 split up into lesser ones, though all derived from the division of 

 any rib may remain together in a fascicle. On the anterior part 

 of the shell the diffusion of the riblets is less defined and regular. 

 All these are crossed by very fine reticulating concentric striae. 

 This is a style of irregular sculpture which with more specimens 

 would probably prove to be cjuite inconstant and is in a measure 

 reproduced in the very variable species from the Oriskany of New 

 York, which we have designated as P. p r o t e u s. A similar 

 aspect is presented by the P. w u 1 f i Freeh from the lower 

 Coblentzian of the Eifel.^ 

 Lozver Devoiiic. Dalhousie, N. B. 



Pterinopecten aroostooki nov. 



Shells subcircular or somewhat transverse with outline slightly 

 extended posteriorly ; beak at the anterior third of the hinge, 

 posterior hinge straight, reaching to the extreme limit of the out- 

 line, posterior wing very slightly extended ; anterior hinge straight, 

 anterior wing moderately large but undulated, an oblique ridge 

 traversing it from the beak just beneath the hinge leaving the por- 

 tion behind it depressed and flat. Below this ridge the ear is de- 



iDevon. Aviculiden Deutschlands, p. 25, pi. 2, fig. 7. 



