SOWFKBY: MARIXK SHEI.I,S of south ATKICA. 13 



Aiikro-post. 16. uinboiifl-inarg. 12 milHni. 

 Hal>. Di/rl'aii. 



A very simple white shell. 



StrMgillia trotteriana Soweiby, n. sp. 



Tesfn latitude subovata, soluUiiSi-ula, ie(jiiivalvis, sidurqni/nUr- 

 a//s, coiivexiuscula, nitida, alba, hiteo iiiicta, prope i/iii/io?ies 

 liiiea, varie et conspicne striata ; stiiis aiiticis concent ricis 

 sub-remoiis ; medianis obliqnis subradiantibiis, cnni siriis 

 anlicis angulum deflectiim fonnantibns : post/cis siib-concen- 

 tiicis, creberrimis, leriter luidutatis. Margo dorsa/is utriiujue 

 dcclivis ; anticus l>revis, lotiindatus, leviter jlexuosiis ; posticus 

 longior, reciiusculus. Cardo normalis. Pagina interna lutca. 

 Antero-post. 12, umbono-marg. 10 millim. 



The striae 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 stria which 

 cover the middle portion to the i)osterior angle, behind 

 which they are again concentric and much closer. This 

 very interesting species was found at I)urt)an by Mrs. 

 Trotter. 



Donax nitidus Deshayes. — Sowb., ''I'hes. Conch.,' vol. iii., 

 p. 3]4, pi. 282, fig. 75. Natal (Burnup). The specimens 

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



Donax lubrlcus Hanle^-. — Reeve, 'Condi. Icon.,' Donax, 



pi. 7, fig. 46. 

 Donax aemulus Smith, 'Proc. Zool. Soc.,' 1877, P- -1^, p'- 



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

 Mactra aequisuicata Sowb., n. sj). 



Testa sub-trigona, ccquivalvis, fere (eqinlateralis, solidiiiscnla, 

 leviter inflata, pallide lutescente-cornea, utrinqtte concentrice 

 dense sulcata ; u/nbones ohtusiusculi, incurvati, purpuieo 

 tincti ; margo dorsalis utrinque decliTts, area latiuscula, 

 planato-convexa, lunula vix conspicua ; margo ventralis 

 arcuatus ; cardo normalis : pagina interna polita, albida, 

 pallide purpiireo-p-iseo fasciatiin tincta. 



Antero-post. j8, umbono-marg. 48 millim. 



Hab. Natal [Burnup). 



