C Y V \{ I i\ A. 



I'l.ATK 1. 



(u-nus CYI'ULNA, Lamarck: 



Tcshi htvalcis, oralis, birniisculona, marina, wquivd/visa, 

 c/nJermide sicbrugo a, crassd indiitd ; umhones 

 airvi ; denies in idraque valvd tres cardinales uno 

 lateralis posticus, remotus. Impressiones muscutares 

 in ulrdqne valvd dual, lateralas distaider'. Imjirr^i^io 

 muscularis pallii intetjer. Liija)/' ' /. 



partim in sinu inarginali imniersuni 



Shell bivalve, oval, bimuscular, iii;iiiii . ■ _i ,,',., 

 • covered with a subrugose, thick ejnderiiiis ; iiiii- 

 boes curved ; three cardinal teeth in each valve, 

 one- posterior, lateral remote. Muscular im- 

 pressions two, lateral distant. Muscidar impressions 

 of the mantle entire. Ligament external, partly 

 inserted in a marginal sinus. 



There apjiears to be really only one recent species of 

 this genus, which belongs to the northern seas of 

 Europe. It is a very Venus-like shell, with the hinge of 

 the Cytheroa group, but having one very long, distant 

 posterior lateral tooth. 



Species 1. (Fig. a, h, M„s. .MacAncirc" 



CyI'UIN.V l.SLANDU', 



/r.s7,; snl... 



solid,;. , 



i„d,ila : 

 ,/,r/iri, n 

 vrntrali 



■'pidermidi: striata, erased. 



latere antico lircvi, 

 liiidiiiiiiliiis arcvatis, pmmih 



late 



/"" 



iihtruncato. 



<idjqiiadrato, 

 'inc dorsali 



TlIK 



.led 



'uvyinc trrm 

 'rcuato. 



li'i:i..\ND Cyri;ix.\. Shell, subov; 

 solid, covered with a thick, striated brown or 

 black epidermis ; anterior side short, dorsal 

 margin slojied, umboes arched, prominent, ven- 

 tral margin convex ; posterior side sulxpiadrate, 

 terminal margin slightly truncated, dorsal margin 

 arched. 

 LiNN^BL-s. (Venus) Systema Natura}. 

 Cyprina vulgaris, Sowerby. 

 Venus burardium. Born. 

 llab. Northern British and Scandinavian Coasts. 



Fig. 1. 

 sulhcienti 



jprescnt; 



ellipti. 



rm not 



