CHAPTER II: THE WATERING-POT SHELLS 

 AND CLUB SHELLS 



Family GASTRocHy^NiD/^ 



Genus ASPERGILLUM, Lam. 



Shell small, both valves cemented to the walls of a trumpet- 

 shaped tube, which bears several ruffles toward the large end; 

 base of the tube is perforated and ornamented with minute tubes 

 containing filamentous mantle processes. Animal elongated; 

 foot fmger-like; siphons two, long, contractile, united; mantle 

 margin thickened, ruffled, reaching to end of tube. Twenty-one 

 species. Gregarious burrowers in sand or mud. Red Sea to 

 Australia. 



The "Watering-pot Shell (A. vaginiferum, Lam.) is a small 

 affair always, but the long trumpet its mantle secretes reaches 

 seven inches in length. The beaks of the two insignificant valves 

 are visible near the base of the tube, where they are imbedded. 

 A strange beast is this which outgrows its bivalve shell, and 

 builds greater after a plan quite distinct from the bivalve pat- 

 tern; all the organs of the body are changed to suit life in the new 

 abode. The mollusks occur in numbers in sand and mud near 

 low water mark; disturbed they retire within their stony citadels 

 whence they are with difficulty extricated. 



Habitat. — Red Sea. 



THE CLUB SHELLS 

 Genus CLAVIGELLA, Lam. 



Shell with right valve free, left imbedded in tube ; tube cylin- 

 drical, frilled above, base bordered with tubuli; mantle frilled, 

 with tentacular processes. Six living and fourteen fossil species. 

 Mediterranean Sea to Australia and Pacific Islands. 



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