S L E N. 



Species 3. (Fig. b, Miis. Nobis.) 



It is thouglit desirable to present this common 

 variety of Solen ensis, because Mr. Dunker seems to 

 have given the name Solen anuma to specimens in the 

 British Museum from Aru Island, which can in no way 

 be distinguished from the British forms. 



Species 4. (Mus. Nobis.) 



Solen marginatus. Sol. testd angrustiusculd, convexd, 

 fulvd ; qndermide tenui; margine dursali recto ; 

 area dorsali lineari, inconspicud ; wed itmhonali 

 lata, subnigosd; margine ventrali medio vix e.c- 

 cavato ; margine postico rt'Ctiitsculo ; margine ant ico 

 obli(juo, elevate, unicoslato, post costaiu caiuili 

 profunda constricto. 



The lioiiUKKED Solen. Sliell rather narrow, convex, 

 fulvous ; epidermis thin ; dorsal margin straight, 

 dorsal area linear, inconspicuous ; uuibonal area 

 broad, rather rough ; ventral margin very slightly 

 excavated in the middle ; anterior margin obliijue, 

 raised, single-ribbed, constricted behind the rib by 

 a deep canal. 



PULTENV. 



Solen vagina, Pennant, non LinnKus. 

 Hab. Britain. 



Species 5. (Mus. Brit.) 



Solen grandis. Sol. testd lata, subco/npressd, pur- 

 purea strigatd, antice subattenuatd ; margine dorsali 

 rectiusculo, ared latiusculd ; margine ventrali ante 



medium paulu angustato, margine postico angusto, 

 sulirotundatim quadrato ; margine antico simplici, 

 valde obl/quo, ad marginem ventraleni oblique aeu- 

 minato. 



The large Solen. Shell broad, subcompressed, striped 

 with purple, anteriorly rather attenuated ; dorsal 

 margin rather straight, area rather broad ; ventral 

 margin a little narrowed before the middle, 

 posterior margin narrow, rather rotindly square ; 

 anterior margin simple, very oblique, obliquely 

 acuminated at the ventral margin. 



Dunker. Proc. Zool. Soc, 18G1. 



Hab. Philippines. 



Broader in proportion than Solen Imncatus ; rather 



narrowed towards the posterior end, and the anterior 



margin more oblique. 



Species G. (Mus. Brit.) 



Solen brevls. Sol. testd reciiiisculd, 2>ostice subcom- 

 planatd et attenuatd, purpurea strigatd ; margine 

 dorsali postic^ subdeclivi ; margine postico angusto, 

 rotunda ; margine antico abrupte truncato. 



The short Solen. Shell rather straight, posteriorly a 

 little flattened and tapering, striped with purple ; 

 dorsal margin posteriorly sloped ; posterior margin 

 narrow, rounded ; anterior margin abruptly trun- 

 cated. 



Gray, in Brit. Mus. 



ILib. American Seas. 



Differing from Solen tnincatus in being sloped or 



tapering towards the posterior end. 



April, 1874. 



