156 SOWERBY : MARINE SHELLS OF SOUTH AFRICA. 



L. capensis Deshayes. This seems to be a distinct species; it 

 is much broader than L. oblonga, and at the same time 

 differs considerably in form and character from L. 

 elliptica. 



Mactra (Schizodesma) Spengieri Gmel. This West 

 African species is seldom found so far south as the Cape. 



Mactra Adam son i Phil. The examination of a number of 

 specimens presenting considerable variation in form and 

 colouring has convinced me that this is specifically the 

 same as M. decora^ of Deshayes. 



Thracia capensis Sowerby, sp. nov. (Plate iii, fig. 4.) 



T. testa elliptica^ subceqinlatera, lev iter inflata, tenuis, con- 

 ce7itrice irregulariter plicata, albida, epidermide pallide 

 stramiiiea indiita, antice obscure biangulata. Umbones aaiti, 

 depressi, incurvati, approximati. Lunula concavo impressa 

 elongata. Cardo normalis ; fovea ligainenti oblique trigona, 

 parva. 

 Diam. antero-post i^ mill. ; umbono-viarg. 12 mill. 



A small thin inflated species submitted to me by Mr. 

 Darbishire. 



Panopea attenuata Sowerby. A single valve of this rare 

 species. 



Crassatella acuminata Sowerby, sp. nov. (Plate iii, fig. 6.) 

 C. testa valde inczquilateralis, donaciformis, leviter coinpressa, 

 crassa, 7'ufo-fusca coticentrice obscure rugata, antice rotutidata, 

 postice producta, acuminata. Umbones parviusculi, vix 

 elevati. Margo dorsalis posticus obscure biangulatus. Cardo 

 normalis. Pagina interna alba,fusca tincta. 

 Diam. antero-post. J^ mill.; umbono-marg. 22 mill. 



An elongated compressed species, remarkably acumi- 

 nated at the posterior extremity. I have only seen odd 

 valves. 



Solen marginatus Pult. Scarcely to be distinguished from 

 British specimens. 



Solen reguiaris Dunker. Several perfect specimens. 



J.C, vi., Oct., i88q. 



