202 Mr. W. Clark on some of the Animals of the Chemnitzise. 



body, a light, corneous, pyriform, obliquely striated operculum. 

 This elegant little creature is very vivacious, and free from shy- 

 ness. 



Habitat : muddy ground, in 10 fathoms water, six or seven 

 miles from the land, off Exmouth. 



It is one of the unrecorded species. 



Chemnitzia ohliqua, Alder. 

 Odostomia diaphana, nonnuU. 



The animal inhabits a very pale yellow-white smooth shell of 

 four rather tumid volutions, besides the apical reflexion, which is 

 less than usual, the divisional lines are by no means oblique, and 

 the body exceeds the length of the spire ; its colour is a brilliant 

 frosted subhyaline white. The mantle is even, except a conspi- 

 cuous tubular fold at the upper angle of the aperture. The 

 rostrum is short and cloven in the centre almost to the eyes ; 

 each segment forms an arcuation to each side equal to an angle 

 of 40°. The tentacula are strong, rather long, without much 

 auriform folding, subrotund and taper, terminating with minute 

 circular snow-white spots or inflations on the tips ; the eyes are 

 close together at the internal basal angles ; the great peculiarity 

 attached to the tentacula is, that instead of a moderate diver- 

 gence on each side the rostrum, they form large arcuations and 

 are carried at right angles with the axis of the shell. Foot thin, 

 rather concave in front, slightly auricled, long and broad, and 

 when fully extended reaches beyond the body whorl, terminating 

 in a distinct bifurcation, which is very apparent in slow march, 

 but on a quicker pace being attained, the fork in some measure 

 decreases in consequence of the greater extension of the foot ; on 

 a small simple lobe, close to the junction of the foot with the 

 body, is fixed an elongated, narrow, corneous, delicate light yel- 

 low operculum with close-set oblique striae of growth. 



Taken at Exmouth from a shelly bottom, six miles from 

 shore, in 12 fathoms water. It has hitherto escaped the re- 

 searches of authors. 



I have thought the " obliqua," if unconnected with the Ch. 

 Warrenii (the C. decorata of authors), a doubtful species, but 

 the above description removes all doubts of its not being in esse. 



Chemnitzia insculpta, JMontagu. 



The animal occupies an ivory-white shell of five moderately 

 rounded volutions, with well-marked but not oblique sutural 

 lines ; the three lower whorls at the basal portions have very fine 

 distant either concentrically circular or spiral strise. The colour 



