ee Ae as 
; 7 
250 LAND AND FRESH WATER SHELLS. 
Vertigo sexdentata.—F ound by Mr. Colley with 
the last, and also by him in a similar situation a 
very short distance from Plymouth. 
Planorbis vortex.—Common in pools and 
streams. 
Planorbis albus.—Common in pools attached to 
plants and stones. 
Planorbis imbricatus.——Rather local. In a 
standing pool near my residence I find them in 
plenty attached to plants. 
Planorbis spirorbis. Found by Mr. Colley in 
pools. Rare. 
Planorbis complanatus. In slow rivers. Con- 
fined according to Dr. Turton, to Suffolk and 
Devon. 
* Planorbis rhombeus.—In slow streams near 
Torquay. 
Limneus pereger.— Very common in pools, 
streams, and rivers. 
Limneus fossarius.—Rather common in streams, 
and pools. 
Physa fontinalis. Not common in ponds, 
streams, and rivers, attached to stones, sticks, and 
other objects. 
Paludina stagnorum.—Very rare in pools and 
streams. I have never procured more than two 
specimens. 
Ancylus fluviatilis—Common on stones and 
plants, in pools, streams, and rivers. 
Ancylus lacustris——Found rarely on aquatic 
plants. : 
4 species of this division of the Molluscs seem to 
be limited to this district. Observations on their 
geography, &c. occur in the next chapter. 
