Xll 



CLASSIFICATION. 



Tectlbranchia, 



Infer obranchia, 

 Nudibranclria, 



Heteropoda, 



Covered-gills, ) Bulk or 

 i. e., by the mantle, j Bubble. 

 Under-gills, i. e., ) ... , 

 under the edge I ff ffj^ 

 of the mantle. ) Diphylhdia. 

 j Naked-gills, i. e., 1 Glaucus, 

 ( without Shells. ) Doris. 

 Other-footed, i. e., feet ) Carinaria, 

 different from the others. ( Firola. 



II. ACEPHALA. HEADLESS MOLLUSKS. Four orders. [like gills.) 



(1). CONCHIFERA (Shell bearing) or LAMELLIBRANCHIA, (Plate or leaf- 

 (Oyster Family) Ostracece- f sub-families-^norauWa?, Anomia. 1 ,, 



I P/acunt^,Placuna.| Monom y- 



OttreidtB, Ostrea. J. 



a &amp;lt;&amp;gt; r 



Aviculide, Avicula. j muscle 



(Fresh Water Mussels) 4 Naiades or t/rnomW#, Unio, Anodon, 



Alasmodon. 

 (Salt-water do. ) 4 Mytilacece, Mytilus, Modiola, Pinna, 



Crenella. 

 4 C/iamaccff-sub-families, 



Tridacnidce, Tridacna. 

 Chamidce, Chama. 

 4 Cardiacece t .( do. Carditidee, Cardita. 



Mantle closed behind. 



Siphons united ] Lucinidtx, Lucina. 



or distinct. I Veneridce, Venus. Dimyaria 



[ Crassitcllidce, Crassitella, (or having 



Sub-order INCLUSA (inclosed, i. e., within the j two 



mantle, which has but one opening for the muscles.) 



passage of the foot.) 



Families Madridce, Hactra. 



Myidce, Mya. 



SolemyidfB, Solemya. 



Saxicavida, Saxicava. 



Pandoridce, Pandora. 



Solenidce, Solon (Razor Shell). 



Pholadidce, Pholas. 



Teredinidce, Teredo (Wood or Ship Worm. 

 Enclosed in a tube ( Tubicolidce, Aspergillum ) or Watering- 

 but not attached. \ Gastrochaena. j pot. 



C Arm-footed, i. e., having two long spiral ^ Terebratula, 

 (2). BRACHIOPODA, ^ arms each side of the mouth capable &amp;gt; Lingula, 

 ( of protrusion. ) Orbicula. 



(8). TUNICATA, \ Coated &amp;lt; l e &quot; bod -^ env eloped in an elastic i __ including 

 | tunic or coa-t, J 



the Ascidi&ns (or Mollusks of a Leathern bottle-shape). 

 Gr. Moss-animals, i. e., largely aggregated like ) 

 corallagineous Zoophytes. ) 



