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POPULAR CONCHOLOGY. 



jecting plate in each valve; ligament external; bosses 

 worn by being placed near each other. Animal, Owen 

 remarks that it is very similar to that of Panopcea* — 1 

 species ; also fossil. 



There is only one species known to be in existence 

 at present, the Pholadomia Candida, which is found after 

 hurricanes at the island of Tortola; it is supposed to 

 be a native of deep seas, and therefore only occasionally 

 thrown up by the waves on to the shores, it is conse- 

 quently scarce. 



Allorisma. King. — Shell equivalve, elliptical, more 

 or less inequilateral, closed, or gaping at both ends, never 

 with radiating ribs, but having the lower edge of the 

 valves strongly wrinkled ; hinge toothless, the ligament 

 placed on two shelly plates, which are lengthened in the 

 direction of the hinge, but which vary, from a hori- 

 zontal to a vertical direction; two muscular impres- 

 sions, which have much the same position as those of 

 Thracia pubescens ; pallial impression with a deep sinus 

 almost like Mya arenaria. — Fossil. 



Edmondia. De Koninck. — Shell lengthened, equi- 

 valve, inequilateral, transverse, oval or rounded, with 

 numerous cross and concentric stripes; the lunule is 

 gaping; the hinge without teeth, their place supplied by a 

 narrow cross, deep lamella, partially concealed by the 

 boss, and probably carrying the ligament. — 2 species, 

 fossil. 



Glycimeris. Lam. (Cyrtodaria Daudin.) — Shell 

 transverse, possessing no teeth, but thick projecting hinge- 

 plates bearing the ligament ; gaping almost all round ; 

 ligament external ; bosses generally eroded. Animal, with 



