206 The Scottish Naturalist. 



seems the most widely spread and commonest of the genus. It 

 has been found as far north as Ross-shire, and is specially com- 

 mon in the highland valleys, where by sweeping the heather, 

 ferns, &c, with a butterfly net, a number of specimens may be 

 easily obtained, the majority of these, however, being immature; 

 in fact mature specimens seem to be rare. It may also be 

 found under stones and among decaying ferns. 



V. cdentula Drap. — This is a local and rather scarce species, 

 though widely distributed. I have generally found it on the 

 sides of big stones, among wet grass, and sometimes among 

 decaying fern leaves. 



V. minuta Stw. — From personal experience I can say nothing 

 regarding this very small and rare species. It has been found 

 at Balmerino in Fife, and on Salisbury Crags, and is said to 

 occur under stones in damp shady places on hills. Possibly it 

 has, from its small size and probably local habits, escaped notice 

 in other localities. 



Caryehium minimum Mull.— This beautiful little shell is by 

 no means rare, though possibly, from its small size, overlooked. 

 It may occasionally be found on or under stones, but more 

 commonly under moss in damp shady places. The easiest 

 way to obtain it in abundance, however, is by sifting decaying 

 fern-fonds in the manner already mentioned. It is found 

 throughout Scotland. 



Melampus bidentatus Mont. — " Under stones that lie close to 

 the ground between tide-marks on many parts of our coast from 

 Shetland to Sark." — Jeffreys B. C. v. 109. Var. alba equally 

 diffused. I know nothing personally of the habits of this or of 

 the two next species. 



M. myosotis Drap. — " Abundantly on mud flats and salt 

 marshes in all estuaries." Var. ringens, in the crevices of rocks 

 on the open sea coast, near high-water mark. (I.e. 107.) 



Otina otis Turt. — Rocks between tide-marks, Arran. (I.e. 1 1 1.) 



Planorbis albus Mull. — A common and widely-distributed 

 species, inhabiting weedy ponds and slow streams. I have 

 found it at an elevation of 1000 feet, but it is not a common 

 highland species. 



P. glaber Jeffreys. — Rare and local, on water plants in ponds 

 and marshes. Jeffreys says, "from Unst to Penzance, but not 

 generally diffused." I have not met with it myself. 



P. naut ileus L. — Said to occur throughout, in ponds and 

 ditches. 1 have only met with it near Perth, where it is rare. 



