BKACH10PODA. 



219 



Kraussia (rubra) Dav. Cape. Fig. 121. K. Lamarckiana, Dav. Aus- 

 tralia. Fig. 120. Shell transversely oblong; hinge-line nearly straight; 

 beak truncated, laterally keeled ; area flat ; foramen large, deltidium rudi- 

 mentary; dorsal valve longitudinally impressed, furnished inside with a 

 forked process rising nearly centrally from the septum; interior often 

 strongly tuberculated. The apophysis is sometimes a little branched, indi- 

 cating a tendency towards the form it attains in fig. 122. Animal with 

 rather small oral arms, the spiral lobe very diminutive. Distr. 6 sp. S, 

 Africa, Sydney, N. Zealand; low-water to 120 fms. 



Fig. 122. Animal. 



Dorsal valve. 



? Megerlia (truncata) King, 1850. PI. XV. fig. 9. Fig. 122. Loop 

 trebly attached ; to the hinge-plate by its crura, and to the septum by pro- 

 cesses from the diverging and reflected portions of the loop. Distr. 2 sp. 

 Medit. Philippines. These species belong to the same natural group with 

 Kraussia. 



? Kingena (lima) Dav. Cretaceous, Europe, Guadaloupe. Valves spinu- 

 lose; loop trebly attached. 



Fig. 123. Ter. (Kingena) lima-, (after Davidson.) 



/. dental sockets rj, cardinal process, c. crura; d. diverging processes of loop ; 

 r, reflected portion ; e. third attachment of loop ; *. dorsal septum. 



