CHAPTER XLI: THE SENTINEL SHELLS 



Family AssmiNiiDi^ 



Shell small, globose-conical, with sharp lip; operculum 

 of few coils, horny, nucleus on the side; gills replaced by a pul- 

 monary sac; tentacles wanting; eyes on very long stalks, and 

 the active mollusks appear to be keeping a sharp lookout for 

 danger. Terrestrial or amphibious mollusks. Found in Europe, 

 Asia and America. 



Genus ASSIMINEA, Leach. 



A. Francesiae, of India, one of the few species of this sole 

 genus in the family, remains on land for days, "looping" along 

 at great speed, exactly like a "measuring worm," using the snout 

 and small foot alternately. The tentacles and the eyestalks that 

 branch from them are of equal length. 



Two Californian species have been reported. 



m 



