co^chylw—dithyra. 26. 



Turton, Conch. Diet p. 163. 

 Solen bidens. Chemnitz, xi. p. 203, tab. 198, fig. 1939. 



Mus. uost, From Dublin bay, and Exmouth. 



Shell nearly half an inch long, and nearly an inch broad, thin 

 and transparent, rounded at both ends and a little contracted in 

 the middle, pale horn-color or covered with a greenish skin, with 

 a reddish longitudinal stripe from the hinge growing fainter and 

 broader towards the margin: inside with a longitudinal rib in the 

 middle ; in one valve two erect teeth, one of which is pointed, 

 the other broad and flattened at the top. 



As both the Solen fragilis and the Tellina fragilis of former 

 authors fall into this genus, it was necessary that the specific name 

 of one of them should be changed : and as the Tellina fragilis is 

 a Linnean and a prior appellation, we have deuorainated this 

 species from the red fillet which proceeds from the hinge in both 

 valves. 



florida. PsAMMOBTA festd ovato-oblongd, sfriis tfdnsversis creht'is lon- 

 gitttdinalibusque minimis. 

 Shell oval-oblong, with close-set transverse strise and minute 

 longitudinal ones. 



Tab. nost. 6, fig. 9. 

 Mus. nost. "Western coasts, and Ireland. 



Shell half an inch long, and an inch broad, rather convex, 

 nearly equally rounded at both ends, variously marked with 

 purple red or yellow zones and longitudinal rays, and colored on 



