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JOURNAL, R.A.S. (CEYLON). [VOL. II., PART II. 



flat, and its mouth is so situated that in this position it can 

 be drawn down close to the object along which the inmate 

 is crawling. Six minute eggs, strung together and fastened 

 to the inner edge of the whorle near the entrance, have been 

 detected by the aid of a powerful glass. 



In company with the preceding was discovered the 

 following, which I have named Bitkinia minima^ from its 

 diminutive size : — 



j Bitkinia Minima. 



The largest specimen found measures three-eighths of an 

 inch in length, one-eighth in breadth ; whorles three, mouth 

 oval, plain, close with an operculum ; colour horny, trans- 

 parent, the animal when alive imparting to the shell a 

 reticulated green appearance. 



Habitat, in company with the preceding, but giving 

 preference to stones and rocks. 



These minute shells are also endowed with the power of 

 crawling along the surface of water ; they start in a similar 

 manner, and progress by alternate expansion and contraction. 

 So great is the hold they retain of the surface, that I have 

 seen one with the whole of the foot even and level with the 

 surface, apparently immovable, and yet the heavy portion 

 of the molusk twisting and twirling round with great 

 velocity to dislodge a fellow swimmer who had made use 

 of it as a resting place. The mouth of the molusk is a 

 small slit on the underside, through which is continually 

 passing and repassing a small stream of water, much aiding 

 it in its movements whilst swimming, which are brisk 

 enough. 



These minute molusks appear to be infested by a singular 

 parasitic enemy, in the shape of a small active blood-red 

 worm, which passes up into the shell and devours the 

 inmate ; in a similar manner the glow-worm feasts on the 

 Cyclostoma of the Kandyan country. 



