210 BULLETIN 91, UNITED STATES NATIONAL MUSEUM. 



tions. Outer surface of the entire shell marked by rather coarse, 

 concentric lines of growth and numerous, exceedingly fine, white, 

 evenly spaced, radiating striations. 



Cat. No. 186945, U.S.N.M., contains four valves of this species 

 from Port Alfred (Coll. No. 315). The one selected as type is not 

 quite a mature specimen, measuring: Length, 41 mm.; altitude, 

 29 mm. 



Genus LUTRARIA Lamarck. 



LUTRARIA CAPENSIS Deshayes. 



There are three lots of this species in the collection of the United 

 States National Museum, from Port Alfred, as follows: Cat. No. 

 187168, two specimens (Coll. No. 715); Cat. No. 249873, one valve 

 (Coll. No. 1145); Cat. No. 251030, another valve (Coll. No. 1547). 



Family SAXICAVIDAE. 



Genus SAXICAVA Bellevue. 



SAXICAVA ARENACEA Smith. 



There are eight lots of this species in the collection of the United 

 States National Museum, all from Port Alfred, as follows: Cat. No. 

 187179, one specimen and four valves (Coll. No. 730); Cat. No. 

 249874, five valves (Coll. No. 1146); Cat. No. 249875, seven valves 

 (Coll. No. 1147); Cat. No. 249876, four young specimens (Coll. No. 

 1148); Cat. No. 249879, two young specimens (Coll. No. 1151); 

 Cat. No. 251046, one valve (Coll. No. 1563); Cat. No. 251054, one 

 valve (Coll. No. 1571); Cat. No. 251057, two valves (Coll. No. 1574). 



SAXICAVA LIRATA Smith. 



Cat. No. 251053, U.S.N.M., one specimen from Port Alfred (Coll. 

 No. 1570). 



Family GASTROCHAENIDAE. 



Genus GASTROCHAENA Spengler. 



GASTROCHAENA, species ? 



Cat. No. 249871, U.S.N.M., contains one worn valve belonging to 

 this genus, from Port Alfred (Coll. No. 1143). It is too poor to be 

 properly identified. 



Family PHOLADIDAE. 



Genus PHOLAS Linnaeus. 



PHOLAS ALFREDENSIS, new species. 

 Plate 44, figs. 1,2. 



Shell elongate-ovate, decidedly beaked anteriorly, marked by 

 numerous very closely spaced, low lamellae and fine radiating riblets 



