﻿1 68 NEW YORK STATE MUSEUM 



but differs from it in the same respect as well as in the less angular 

 termination of the umbonal ridge and in having the ventral and 

 dorsal margins more nearly parallel. 



Edmondia magdalena nov. 



Shell small, oblique, very elongate for the genus, nearly twice as 



long as high. Umbones inflated, protruding above the hinge which 



is nearly straight and extending about six-tenths the 



length of the shell. Posterior margin subtruncate, 



rounding below into the elliptical ventral border 



Edmondia mag- which continues in an elliptical curve to the hinge. 



dalena nov. X2 *■ . • o 



Cast of left valve. Beak 2 mm from the anterior end of the hinge. The 



Cape le Trou ° 



Grindstone i. details of ornamentation are not well shown on the 

 cast, but there are fine, even concentric striae and the usual undu- 

 lations of the genus. 



Dimensions. Length, 9+mm ; height, 5+mm ; hinge, 6+mm. 



Remarks. This species is similar to E. h a r 1 1 i Dawson, but is 

 much smaller and the hinge slopes less steeply anteriorly, and it is 

 slightly more truncated on the posterior end. 



Parallelidon hardingi Dawson? 



M a c r o d o 11 hardingi Dawson. Acadian Geology, p. 302, fig. 102, 



1878. 



One small specimen probably belongs to this species. It is on a 

 slab with Sanguinolites insecta Daw. 



Parallelidon dawsoni nov. 

 Shell small, subquadrangular, beaks very convex and. 





Paralleli - 



arched over the cardinal area. Anterior end short, don ha r- 



dmgi Daw- 



abruptly rounding' downward and backward into the gently son. Wmd- 



r J ° % ° sor, N. S. 



sinuate ventral margin. Posterior lateral edge evenly and 

 abruptly rounded into the truncated posterior margin which reaches 

 the hinge at a slightly obtuse angle, the anterior and posterior 

 borders being nearly parallel. The length of the 

 hinge is equal to the length of the shell and its 

 P^ direction nearly parallel to the ventral margin. 

 Parallelidon daw- The cast shows fine concentric lines and larger 

 T?o^G°rIndS a o P n e e i e growth varices. 



Dimensions. Length, 13.5 mm; height, 7 mm; beak, 4.5 mm 

 from front. 



Remarks. In illustrating his species, P. h a r d i 11 g i, Dawson 

 used two specimens, one (fig. 102a) a very short, highly gibbous 

 specimen, quite convex beneath the beaks and on the ventral margin 





