xxxvi. coisc ay LI A—DrrHYR A. 



16. siiiuosa, sinu longilmlinali ab umbone. 



with a longitudinal sinuosity from the beak. 



17. aurea, medio iumido, lateribus attenuatis. 



tumid in the middle, and tapering to the sides, 



It latere antico angiilafo. 



angular at the anterior side. 



18 virginea, sliiis trmisversis planatis antici laiioribus. 



with flat transverse strife which are broader at 

 the anterior side. 



19. nitens, viedio Iumido, striis absoleth reticidatis. 



tumid in the middle, and obscurely reticulate. 



20. decuss^ta, striis decussatis antich tuberculosis, dentibus dnobus 



Jissis. 



with decussate slriiL' whicii are tubercular at tlie 

 anterior side, and two of the teeth cloven. 



21. Piillastra, striis decussatis minutis autice rugosis, deiite luiico 



fisso. 



with minute decussate striaj which are rough at 



the anterior side, and one of tlic teeth cloven. 



37. CVTHEKEA. 



1. Cbione, ovato-cordata nitida,. 



oval heart-shaped and polished. 



'2. Guineensi?, obliqnh cordata, laminis iransversis subimbricatis. 

 obliquely heart-shaped, with transverse and some^ 

 >vlmt imbricate plates. 



