PL. XX. 



.. ;r fc 



/a 





n 



w 



Q 



1. 1 f* Arwrma ephippWMW . f. formed on, at' Pe.cten<. I 9 vas\ 

 CLCuLe.outau I. * foramen, closed by shellv ptaitf*. / ? . plus* . 

 Z. 2 U A. pcutzUiJbrmijs . 2 b var. stricubou. 2 f>l.uy. 



West, isny CrF.So werty. 



