CONCHYLIA— D/THFiJ^. xxxvii. 



3. exoleta, orbiculo-cordata depressa, striis transversis capillaceisl 



orbicular heart-shaped and flattish, with trans- 

 verse capillary striae. 



4. sinuata, obovato-cordata tumida, striis transversis capillaceis. 



oboval heart-shaped tumid, with transverse 

 capillary striae. 



5. Tigerina, orbiculo-cordata, striis decussatis. 



orbicular heart-shaped, with decussate striae. 



38. Akca. 



* margine interna creniihio. 

 with the inner margin toothed. 



1. Noae, angulo marginis superi productiori. 



with the angle of the upper margin longer. 



2. fusca, angulo marginis superi brevicri. 



with the angle cf the upper margin shorter. 

 3 tetragona, subtetragona, casta longitudinali. 



nearly square, v/ith a longitudinal rib. 



4. reticulata, costis longitudinalibus barbatis decussatis. 



with bearded decussate longitudinal ribs. 

 ** margine interna integerrimo. 

 the inner margin very entire. 



5. perforans, latere antico angulato. 



angular at the anterior side. 



39. Pectunculus. 



