168 



from the apex to the basal margin. >S'. radiatus, Linn. (Grenus 

 Siliqua, Megerle ; Leguminaria, Schum.) 



B. More cylindric and destitute of the interior rib. S. strigiUa- 

 tus, Linn. 



C. More elongated and subcylindric. >S'. legumevi, Linn. 



These species shew the connection of the two genera to be inti- 

 mate ; but there is certainly a great difference in habit, which, in 

 conjunction with the notable characters of the rounded form of 

 the muscular impressions, the distance of the hinge from the ex- 

 tremity, &c., in the present group, seem to justify its separation 

 from Solen. Like the species of that genus, these reside in the 

 sand on the sea shores, secluded from observation. 



SoLECURTUS COSTATTJS. — Specific character. Hinge nearly 

 equidistant from the posterior termination of the shell and the mid- 

 dle of the hinge margin. PI. 18. 



Solen costatus, nobis. Journ. Acad. Nat. Sci. vol. 2, p. 315. 



FuLGUR. — Shell pyriform ; spire very short ; varices none ', body 

 whorl very large ; aperture large, oval, extended towards the base 

 into an elongate conic,- open canal, which is entire at base ; um- 

 bilicus none ; epidermis deciduous ; labium concave with a single 

 fold or oblique groove near the origin of the canal and a slight 

 calcareous deposition above ; labrum simple : within having eleva- 

 ted striae which do not revolve far within the shell, nor do they 

 reach the edge of the labrum, but leave a smooth border ; opercu- 

 lum horny. 



Ohs. This genus was formed by Montfort. Linn6 placed all 

 the species with which he was acquainted in his great genus Hfiirex. 

 Bruguieres, Lamarck and Blainville referred them to Pi/rula, a 

 genus with which they are certainly very closely allied, but from 

 which they differ in having a fold on the labium, in not being 

 vesicular and thin, in having elevated lines or stria3 within the 

 labrum, &c. Linn6 did not even perceive this alliance, if we may 

 judge from the fact that he placed these shells with Murex, as 

 above stated, whilst he referred the true Pt/rulx to his reservoir 

 Bulla. We do not know what difference exists between the ani- 

 mals. Naturalists do not appear to know whether or not they are 

 operculated, but we can affirm with certainty that the operculum 

 exists in the present genus. When recent the surface of the shell 



