RISSOA. 139 



profoundly impressed, rather oblique suture, and terminate 

 in a small moderately pointed apex. Their longitudinal 

 increase is gradual, and in the medium shaped specimens 

 they are of moderate length, that is to say the penult turn 

 is rather more than twice as broad as it is long ; the more 

 abbreviated is the general form, the shorter of course 

 become the whorls, and vice versa : in the more character- 

 istic examples, the swell of each volution is all but sym- 

 metrical, that is to say, equal in extent both above and 

 below. The body, which occupies from one-third to two- 

 fifths of the entire length, is well and more or less abruptly 

 rounded at its basal declination. The spire (viewed ven- 

 trally) is always half as long again as the mouth, and more 

 frequently about twice its length. The aperture, whose 

 well rounded anterior termination is rather below the basal 

 level of the body-whorl, has an ovate or rounded ovate 

 figure, and is not distinguished by any peculiar colouring ; 

 its posterior contraction is rather slight, and not acute. 

 The peristome is continuous or very nearly so, and is at 

 times almost detached. The outer lip is simple, acute, and 

 semicircular ; it does not expand, neither does it recede 

 nor advance in any perceptible degree towards the base, 

 near which the swell is most marked. The arcuation of the 

 inner lip is much inferior to that of the outer one ; the 

 pillar occupies a considerable portion of it. The columellar 

 lip is thin, narrow, raised at the edge, curved and re- 

 flected ; there is a more or less distinct hollow or umbilical 

 crevice. The throat, as is usual in this section, is quite 

 smooth. Our larger specimens are nearly a quarter of an 

 inch long.* 



* It is possible that the Turbo disjunctus, described by Montagu, and figured 

 by Laskey, who picked it up on Belton sands, near Dunbar, was only a loosely 

 coiled specimen of this or some other well known species. The ni.ignified 



