122 MOLLUSCA. 



DAIDEMA, Ranz. 



Where the tubular portion is almost spherical, and which has but 

 two small valves almost hidden in the membrane which closes the 

 operculum. The opercular valves would not effectually closes the 

 orifice without the membrane which unites them. 



They also live on the Balaenae, and Otiones are frequently observed 

 attached to their surface *. 



* Lepas diadema, Chemn., VIII, xcix, 843, 844. 



