108 THE ELEMENTS 



common shell we have, and well 

 known by the name of muscle. 



Linn. Trans. vcV. viii. page 105. 



/ The cartilage, v v length of the 

 shell, uu breadth of the shell. 



Fig. 5th.— CHAMA COR. Shell 

 sub-globose, beaks recurved ; anterior 

 slope with a gaping fent, slightly 

 wrinkled transversely, covered with 

 a terra sienna coloured epidermis; 

 umbo large and prominent, much con- 

 torted or incurvated, and turned to 

 one side, and not touching when the 

 valves are closed ; hinge strong, teeth 

 ilattisk Inside smooth, white; margin 

 plain. This is a very scarce British 

 shell; and has been found off the North 

 Foreland, the Hebrides, and off St. 

 Abb's Head by Captain Laskey. 



Linn, Trans vol. viii. page 90. 



o Disk, rr beak. 



Fig. Gth.-MYTILUS EDULIS. 

 See description at fig. 4th. 



$ The hvssus or beard, tt seam, 



