PLATE XX— Continued. 



RAFINESQUINA, gen. nov. 



Page 2S1. 



Eafinesquina alternata, Corn-ad. 



(See Plate VIII.) 



Fig. 27. The interior of a brachial valve, with sharply defined anterior and posterior adductor seai-s, and 



showing faint traces of recurving vascular sinuses. 

 Fig. 28. The interior of a pedicle-valve, in which the muscular scars have their normal character. 

 Hudson River group. Cincinnati, Ohio. 



STROPHEODONTA, Hall. 



Page 284. 



STEOPnEODONTA PROFUNDA, Hall. 



(See Plate XIII, figs. 1-5.) 



Fig. 29. An internal east of the pedicle- valve ; showing the broad flabellate diductor .scar.s, meeting in front 



and enclosing a i-ather broad pair of adductoi's. 

 Fig. 30. An enlargement of the muscular area of the brachial valve. X 1^. 

 Fig. 31. The surface strife. X 2. 



Niagara limestone. Near Milwaukee, WiscoTisin. 



STROPHOMENA, Eafinesque (de Blainville). 



Page 445. 



Strophomena Conradi, sp. nov. 



(See Plate XI A, fig. 3.) 

 Fig. 32. The profile of a specimen showing only the upper or brachial valve. 

 Fig 32a. Outline profile of the same specimen. 



Trenton limestone. Treiiton Falls, N. Y. 

 Fig. 33. Outline profile of figm-e cited. 



