CLASÖ I 



PELECYPODA 



493 



Recent ; represented by about 200 fossil and as many recent species. Very numerous 

 siib-divisions have been proposed ; Venus s.s. is typified by V. mercenaria Lam. 



Venus cinda Eichw, 



Fig. 808. 

 Miocene ; Gainfahrn, near Vienna. 



Fig. 809. 



Meretrix semisulcata Lam. 

 Bocene ; Grignon, near Paris, 



Meretrix Lam. {Gytherea aiict.) (Figs. 809, 810). Hinge with lateral teeth. 

 Macrocallista Meek ; Callocardia Adams ; Saxidomus Conrad. Tertiary and Recent. 



Meretrix inciussata Sow, 



Weinheim, near Alzey. 



Fig. Sil. 



Circe exiviia 

 Hoernes. Miocene ; 

 Bnzesfeld, near 



Vienna. 



Tivela Link. Hinge with supplementary cardinals. Miocene to Recent. 

 h. Girce Schiim. (Fig. 811). Gafrarium Bolten. Umbones compressed, sculpture 

 often divaricate, ligament immersed. Tertiary and Recent. 



Subgenus Gouldia Adams. Sniall, concentrically striated. 

 Eocene to Recent. 



Ptychomya Agassiz. 

 Cretaceous. 



c. Paphia Bolten 

 (Tapes Megerle ; Pul- 

 lastra Sow.) (Figs. 812- 

 814). More or less 

 elongate, oval, with 

 narrow hinge - plate, 

 divergent and often 

 bifid cardinals, no la- 

 terals, and deep pallial 

 sinus. Cretaceous to 

 Recent ; about 150 

 living species. 



Flu. Sl-J. 



Paphia gregaria Partsch. 

 Sarmatian Stage ; Wiesen, near 

 Vienna. 



Fig. 813. 



Paphia (Baroda) fragilis (d'Orb.). 

 Upper Cretaceous ; Gosau, Austria. 



