SOLENACEA. 357 



Chemists assert that light is essential to the full clevelop- 

 meut of colour in birds and flowers; hence the glorious 

 tintings of both in tropical regions, and the gradual sober- 

 ing of colour towards the poles. But this law does not 

 universally prevail among the mollusca. Many shells, 

 brought up by dredging from a great depth, concealed 

 even among the mud, or imbedded in sand, present the 

 colours of the rainbow. We cannot understand the reason 

 why it has pleased the Most High that shells of surpassing 

 beauty should be found, not only in the depth profound, 

 amid groves of coral and sea-weeds, but in mud or coarse 

 sand. We alone know that all His w^orks praise Him, 

 however minute or concealed. " He has made all things, 

 and for His pleasure they are and were created.''' 



family XYI. Solenacea. 



No theme more cm-ious than the perfect order 

 That doth prevail wherever life extends. 



The shell of the Solenacea, though generally elongated 

 or cylindrical, varies considerably in form, as also in the 

 number and position of the teeth, which, in some instances, 

 are wholly wanting. It is generally gaping at both ends. 



