38 



SHELL GALLERY. 



rose), two small valves will be seen imbedded in the surface. 

 They are found with the rose downwards buried in mud or sand at 

 low water on the shores of the Indian and Pacific Oceans. 



J ■' 



Fig. 27. 



a 



Fig. 26. Watering-pot Shell (Brechites vaginiferum) : a, bivalve shell of the 



very young animal. 

 Fig. 27. British IJazor-shell (Solen siliqua) : a, foot ; b, mantle ; c, inhalant 



siphon ; d, exhalant siphon ; c, shell. 



TCase 20 Many of the Solenida, or Razor-shells, possess very elongated 



d-f.] shells, and are remarkable for the great development of the foot, 



which can be pointed or contracted as may be required for boring 

 into sand. By means of this powerful foot the animals, when 

 disturbed, bore with such rapidity and to such a depth that their 

 capture is a matter of great difficulty ; and even when seized they 

 hold on so tightly that at times they suffer their foot to be torn off 

 rather than be captured. They not only burrow in sand, but also 

 have the power of darting through the water, like the Scallops. 



