BIVALVES. — PINNA. 



75 



PINNA— ^-ca JFlng. 



Division I. 

 Rudis — Rough. 

 *Pectinata — Sphuj-ribb'd. 

 Inflata — Inflated. 

 ♦Carnea — Flesh-colour'' d. 

 Rigida — Rigid. 

 Nobilis — Great. 

 Muricata — Prickly. 



Shells longitudinally ribbed. 



Adusta — Pear-shap'd. 

 Vexillum — Banner. 

 Squamosa — Scaly. 

 Vitrea — Brittle. 

 Papyracea — Paper. 

 Saccata — Satchel. 

 Cancellata — Cancellated. 



Division II. — Shell nearly smooth and plain. 

 Nigra — Black. Bicolor — Two'Colour'd. 



*Ingens — Scotch. Incurva — Incurved. 



Rotundata — Giant. Digitiformis — Finger-shap'd. 



Lobata — Lobed. 



£2 



