32 MULTIVALVES. PHOLAS. 



FAMILY 4. Having a cup-like appendage at the base. 

 Galeata Helmet-like. *Spongeosa Spongy. 



FAMILY 5. Tubular and truncated at both ends. 

 Tracheaformis Windpipe. 



DIVISION II. SHELLS ATTACHED TO A FLESHY PEDUNCLE. 



FAMILY 1. Having more than five valves, and a wreath of 



smaller ones round the base. 



Mitella Mitred. Scalpellum Knife- like. 



Pollicipes Cornucopia. 



FAMILY 2. Having only five contiguous valves. 

 Anserifera Striated. Fascicularis Bladder-like. 



*Anatifera- Duck Barnacle. Vellosa Downy. 

 Dorsalis Wrinkled. Dentata Toothed. 



*Sulcata Furrowed. 



FAMILY 3. Having minute and distant valves placed on the 



fleshy extension of the peduncle. 

 Aurita Eared. Vittata Ribband. 



PHOLAS. STONE-PIERCER. 



Animal an Ascidia : Shell having two primary valves, di- 

 varicate, with several smaller differently shaped acces- 

 sory valves at the hinge; hinges recurved, united by a 

 cartilage; in the inside, beneath the hinge, is an incurved 

 tooth. 



IT appears that hitherto only twelve species of this ge- 

 nus have been enumerated, and some of those are so alike, 

 that in many instances they may be considered as mere va- 

 rieties, rather than different species; however, they all pos- 



