CHEMNITZIA. 423 



with interstitial short transverse lines ; the general aspect as 

 to colour is pale azure-hyaline, irregularly aspersed with 

 snow-coloured opake flakes. The rostrum proceeds from the 

 coalescing tentacular membrane, forming a sort of head-veil 

 to a little beyond the foot ; it is long, flat, and terminates in 

 two arcuated lobes with a wide central indentation between 

 them ; the proboscidal orifice is not quite at the extremity of 

 the rostrum, but is placed on its upper surface. The tenta- 

 cular veil, originating in the basal coalition of those organs, 

 is entire, and diverges into two very short, flat, broad, bevelled, 

 subtriangular tentaculiform processes rounded on the tips, on 

 each of which there are about nine intense-white subcircular 

 minute flakes. The eyes are not on the triangular bases of 

 the tentacula, but a little posterior to their origin, imbedded 

 in the skin of the anterior base of the neck exactly behind 

 them ; that is, it can scarcely be appreciated if the inclination 

 be external or internal. The foot is large, moderately long, 

 auricled in front, bevelled to a very fine edge, and when in 

 the fall extension of march tapers to a point, when at rest it 

 is rounded ; it is flat, of thin texture, of a pale blue-hyaline 

 colour, suffused with opake snow-white matter ; it carries on 

 a simple, scarcely raised operculigerous lobe, situate quite at 

 the middle, or at the junction of the pedicle of the foot with 

 the body, an oblong-oval light corneous operculum, with a 

 depressed point as a nucleus, from which oblique striae of 

 increment proceed. The branchiae, buccal apparatus, and 

 the organs of reproduction were not seen, as the shells 

 could not be destroyed, and it is probable that their minute- 

 ness would have caused any attempt to detect them to end 

 in failure. 



There is no tooth on the columella of this species, as in 

 most of the preceding ones, but there are sometimes within 

 the aperture of the ultimate volution one or two minute 

 denticles, as in Conovulus denticulatus, and we have the 

 C. acicula with a decided pillar fold. These columellar ap- 

 pendages cannot at all be depended on from their instability 

 and variableness ; they may serve as a kind of mark to distin- 

 guish one species from another conchologically, but even that 



