A CH A TINA. 183 



eyeless, lower pair consisting of minute and nearly invisible 

 bulbs ; foot compressed, ending in a pointed tail. 



Shell cylindrical, tapering, thin, transparent, very glossy, 

 white, with exceedingly faint, close-set spiral striae, which are 

 only visible under a microscope, to the naked eye the surface 

 appears quite smooth ; peripheiy rounded ; epidermis excess- 

 ively thin ; whorls ^\ to 6, compressed, rapidly enlarging, body 

 whorl occupying about half of the length of the shell ; spire 

 with an obtuse and rounded apex ; suture somewhat deep, 

 oblique ; mouth somewhat pear-shaped, acutely angulated above, 

 deeply notched at the base; outer lip thin, flexuous, except 

 towards the pillar, where it is thick and curved : inner lip 

 a mere film spread on the base of the penultimate whorl ; 

 umbilicus wanting. 



Inhabits many parts of Great Britain and Ireland, 

 at the roots of grass and trees, and in gravel pits. 

 This remarkable mollusc is destitute of eyes. It 

 lives underground, usually at a depth of several 

 inches ; occasionally, however, it ascends to the sur- 

 face. In Yorkshire it has been found in ancient 

 Saxon coffins. In consequence of its subterranean 

 habits, this little mollusc is not easily found in a 

 living state ; its food is supposed to consist of animal 

 matter. 



SECTION II. 



FAMILY IV.— CARYCHIID-a:. 



Body spiral, capable of being entirely contained within the 

 shell; mantle covering the front part; snout produced; eyes 

 seated at the hinder base of the upper tentacles, which are con- 

 tractile ; lower tentacles rudimentary ; foot oblong. 



Shell spiral, elongated ; mouth oval or somewhat ear-shaped, 

 provided with teeth ; umbilicus very small. 



The CarychiidcB resemble the LimnceidcE in having 

 contractile tentacles, as well as in the position of 



