376 SOWERBY : MARINE SHELLS OF SOUTH AFRICA. 



Antero-post. i6, umbono-marg, 12 millim. 

 Hab. Durban. 



A very simple white shell. 



Strigillia trotteriana Sowerby, n. sp. 



Testa rotunde subovata, soliJmsada, cequivalvis, subiequilater- 

 alis, convexiuscula, nitida, alba, liiteo tinda, p7'ope timbones 

 lutea, varie et conspicue striata ; striis antlcis concentricis 

 sub-remotis ; viedianis obliqiiis subradiajitibiis, cum striis 

 anticis angulum defiectum fonnantibics ; posticis sub-concen- 

 tricis, creberjimis, leviter uudulatis. Alargo dorsalis iitrinqiie 

 dedivis ; anticus brevis, rotundatus^ leviter flexuosus ; posticus 

 longior, rediusculus. Cardo normalis. Pagijia interna lutea. 



Anteropost. 12, umbono-marg. 10 millim. 



The strise are not so close as in S. carnaria ; those on 

 the anterior side (nearly half the valve) are nearly con- 

 centric, and form an angle with the oblique striae which 

 cover the middle portion to the posterior angle, behind 

 which they are again concentric and much closer. This 

 very interesting species was found at Durban by Mrs. 

 Trotter. 

 Donax nitidus Deshayes. — Sowb., 'Thes. Conch.,' vol. iii., 

 p. 314, pi. 282, fig. 75. Natal (Burnup). The specimens 

 of this species in the British Museum are from E. Australia. 



Donax lubricus Hanley. — Reeve, 'Conch. Icon.,' Donax, 



pi. 7, fig. 46. 

 Donax semulus Smith, 'Proc. Zool. Soc.,' 1877, p. 271, pi. 



75, figs. 23-25. Durban (Captain Turton). 



Mactra sequisulcata Sowb,, n. sp. 



Testa sub-trigona, cequivalvis, fere cequilateralis, solidiuscula, 

 leviter in-flata, pallide lutescente-cornea, ntrinque concentrice 

 dense szdcata ; uinbones obt^isiusculi, incurvati, purpureo 

 tindi ; margo dorsalis 7ttrinque dedivis, area latiuscida, 

 plafiato-co?wexa, lunula vix conspicua ; margo ventralis 

 arcuatiis ; cardo normalis ; pagina interna polita, albida, 

 pallide purpu7-eo-griseo fdsciatim tinda. 



Anteropost. ^8, umbo7io-marg. 48 vnlli7n. 



Hab. Natal {Bur/itip). 



J.C., vii., Apr. 1894. 



