40 POPULAR BRITISH CONCHOLOGY. 



ing where the foot protrudes. The ejecting siphon 

 has a white membranous tube projecting beyond the 

 fringe; and the only colour, excepting pale yellow, 

 about the little creature consists of a red edge to the 

 openings of the siphons. The shell is oval ; it has one 

 very deep curved valve, and one smaller and flatter; 

 " the front side is rounded, the hinder side is truncated. 

 All the sorts liave the beaks prominent, and the sur- 

 face ridged in the direction of the lines of growth. 

 The hinge has a pit for part of the ligament, and one 

 strong curved tooth in one or both valves. The species 

 of Corhula found in Great Britain are — 



C. nucleus: which is not uncommonly hauled up in the 

 dredge, but is not very often met with by those who 

 can only conchologize on the beach. 



C. rosea is not likely to trouble the collector, but if he 

 should be fortunate enough to find a specimen, he may 

 know it by the rosy hue of its tips, and the compara- 

 tive equahty and smoothness of its valves. 



C. ovata : admitted with doubt among the British fauna. 



II. Sph^nia. — The animal resembles that of Corbula, but is 

 apt to burrow, in which case irregularity of form, and 

 extension of the hinder end, take place. The shell is 



