440 PYEAMIDELLID^. 



simulate the ear-shaped folds characteristic of those organs, 

 which in this species are conspicuous, but the proteiform tips 

 are only slightly developed. The eyes are very black, not 

 quite close to each other, and immersed a little posterior to 

 the internal bases of the tentacula. The foot is rather long, 

 extending to two volutions, very thin, in front bluntly auricled, 

 terminating, when in full march, in an acute point, and carry- 

 ing, on a simple lobe at the junction of the foot with the body, 

 a pyriform, light corneous operculum, marked with arcuated 

 oblique striae of growth. 



The animal is free, creeps with rapidity, and dwells in 

 muddy ground mixed with shelly spoil in 14 fathoms water, 

 off Teignmouth, Devon. This species has never before been 

 observed alive. 



I have examined several live specimens of that variety of 

 the present species termed by authors Eulimella affinis, and 

 I find that the animals of the two are identical -, the only dif- 

 ference is in the shell, which in the " affinis " is more taper, 

 and has the whorls more rounded and better defined by the 

 divisional lines. 



CH. FENESTRATA, Forbes. 

 Ch.fenestrata, Brit. Moll. iii. p. 249, pi. 93. f. 6, 7 ; and iv. p. 277. 



Animal inhabiting a longitudinally-plicated and spirally- 

 ridged, white shell of eight rather flat volutions, which bevel 

 from their bases to the sutural lines ; the apex has the usual 

 reflexion of the tribe. The general colour of the external 

 organs is a subhyaline frosted-white, the internal posterior 

 volutions are a deep red-brown. Mantle even with the aper- 

 ture, except a small shoot at the upper angle. Rostrum 

 slender, long, flat, barely hollowed at its termination. The 

 tentacula are comparatively long and slender; they fold after 

 the characteristic manner of the tribe, and have the white 

 inflated tips; they are united at the bases, on which, close 

 together, 'are imbedded at the internal angles the conspicuous 

 black eyes. The foot in slow march is short, broad and obtuse, 

 but when the pace is accelerated, it becomes attenuated and 



