CHAPTER II : THE WATERING-POT SHELLS 

 AND CLUB SHELLS 



Family Gastroch^nid/E 



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 finger-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. 



310 



