33 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. 



PoUicipes — Cornucopia. 



Family 2. — Having only five contiguous valves. 

 Anserifera — Striated. Fascicularis — Bladder-like. 



*Anatif'era — 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- 



