124 



neighbourhood of Versailles, C. lamettosa, but in this we think he is mis- 

 taken. 



Species. 



1. cselata, Adams. 3. fimbriata, Lam. 5. Sowerbii, Reeve. 



2. elegans. Desk. 4. scitula, Adams. 



Figure. 



Corbis Sowerbii. PI. 37. Fig. 201. Shell, with the left valve showing 

 the elaborately latticed external sculpture, the right valve the show- 

 ing the hinge. 



Genus 5. TELLINA. 



Animal; ovate, compressed, mantle entirely open in front, its mar- 

 gin fimbriated ; siphons long, separate throughout, usually nearly 

 equal, thin, orifices plain or very indistinctly toothed ; foot large, 

 triangular, compressed, apiculate. (Forbes.) 



Shell ; transverse or orbicular, nearly equivalve, moderately in- 

 equilateral, posterior side mostly flexuously beaked, ventral 

 margin often irregularly fiemwus ; hinge composed of generally 

 two card*ncf teeth in each valve, and two lateral teeth, often 

 remote and sometimes icanting. 



There are few mollusks so generally distributed over the globe as the 

 Tellens. The species are numerous, and from the arctic to the equatorial 

 seas the genus is represented in one form or another according to latitude 

 and depth of habitat. The animal is distinguished by a longer and more 

 widely separated pair of siphons than we have yet met with in the bivalves, 

 and one is generally longer than the other. The foot, as in Donas, is well- 

 developed, bent, and apiculated.* The shells do not vary very materially 

 in form, their general characteristic is to have the posterior side, that is, 



* " When the bend in the foot of a bivalve is considerable, forming a sort of elbow, the ani- 

 mal is projected forwards by a succession of short leaps. Such a structure characterizes the 

 Tellince and Donacida. When it is about to make a spring, it firstly, by appropriate motions 

 of the foot, puts the shell on the point or summit, as if aware that this is the position most fa- 

 vourable of any to avoid the resistauce which the sand opposes to the motion. It then stretches 

 out the leg as far as possible, makes it embrace a portion of the shell, and, by a sudden move- 

 ment similar to that of a spring let loose, it strikes the earth with its leg, and effects the leap." 

 — Johnston, fide Reaumur and Smellie, Introd., p. 136. 



