Mollnsca in the Collection of the Zoological Society. 373 



*Harpa gracilis. 

 H. testd oblongd, gracili, costis distantihus, muticis, l(Bvigatis ; long. 



1-pV, lat' T-01 poll- 

 Hah, 



An unique specimen of this remarkably slender Harp is in Mr. Bland's 

 collection. It is white, varied with pale rose colour, and on the ribs are 

 a few small transverse brown lines. 



Trichotropis.* 



Testa U7iivalvis, turbinata, carinata, tenuis, aperturd longitudinem 

 spires superante, basi integrd, columelld ad basim oblique trun- 

 catd, labia externa tenuissimo, acuta. Epidermis carnea, super cor- 

 rinas testes erinacea. Operculum carneum, parvum, lamellis el- 

 lipticis confertum, nuclea laterali. 



The shell may be characterized as being turbinated, and carinated ex- 

 ternally ; its aperture is wide, but still longitudinal, and it is rather longer 

 than the spire ; its base is entire, without any notch, although immedi- 

 ately below the obliquely truncated base of the columella there is an 

 indistinct canal. The whole shell is thin and delicate, its outer lip par- 

 ticularly so. Epidermis homy, forming numerous sharp-pointed bristle- 

 like processes on the edges of the carinse outside the shell ; very strong 

 and by its contraction in drying frequently breaking the edge of the lip. 

 Operculum horny, much smaller than the aperture, composed of ellipti- 

 cal laminse, its apex or nucleus lateral. 



The animal in most particulars resembles a Buccinum as to its exter- 

 nal form and characters, differing from it principally in having only a very 

 small fold of the mantle to line the nearly obsolete canal of the shell. 



This and some other inequalities o£ the edge of the mantle corres- 

 ponding in position to the keels on the outside of the shell, constitute 

 the whole of the differences observable between the soft parts of the 

 animals. 



It may not be improper to add a short explanation of the characters 

 by which the present genus may be distinguished from others with which 

 it has either been confounded or to which it may be related. These are 



* 9pt^ seta, rpoiriQ carina. 



