Mr. Jeffreys on the Mollusca of the Upper Harz. 349 



Zua lubrica, var. pallida and var. gracilis. With the last ; not 

 uncommon. 



Clausilia plicata. On the castle-walls at Stolberg ; not common. 



C. biplicata, and var. alba. On rocks near Alexisbad ; local. 



C. plicatula. On rocks and trees at the same place; common. 

 The authors of the ' British Mollusca ' were mistaken in referring 

 the C. Rolphii of Gray to this species. The form, sculpture, and 

 dentition of each of these species are very different ; and they have 

 been properly separated by Moquin-Tandon in his valuable work on 

 the French land and freshwater Mollusca. 



C. dubia. With the last, and equally common. Whether it is 

 specifically distinct from C. nigricans is, however, questionable. 



C. parvula. On rocks in the woods at Alexisbad ; common. 



Balea fragilis. On rocks and trees near Alexisbad ; not un- 

 common. 



Vertigo pusilla. In the woods at Alexisbad ; not uncommon. 



V. edentula. With the last ; rare. 



V. alpestris. Under stones and on moss in the same woods ; rare. 

 This is a true Vertigo, and has not the slightest vestige of the lower 

 pair of tentacles. The animal is of a light straw-colour, and differs, 

 besides, from that of V. pygmcea (which is not uncommon in the 

 same locality) in having a longer foot and tentacles. It is the Pupa 

 Shuttleworthiana of Charpentier, as previously identified by me 

 (Ann. Nat. Hist. 3rd ser. vol. ii. p. 132) ; but I much doubt its being 

 the Vertigo alpestris of the late Baron Ferussac. Two specimens 

 from his collection (only one of which, however, is entire) are pre- 

 served in the Jardin des Plantes at Paris, and labelled in the author's 

 handwriting "Vertigo alpestris, nob., 4 D., Charp. No. 9. Alpes." 

 In these specimens the longitudinal striae are scarcely perceptible 

 under a lens having a quarter-of-an-inch focus ; and the shells are 

 smooth, thin, and glossy in appearance. I am inclined to consider 

 these specimens, and consequently the V. alpestris of Ferussac (which 

 is a mere MS. name, although adopted by Mr. Alder), to be a variety 

 of V. pygmcea. 



V. minutissima. Under stones at Harzgerode and Falkenstein ; 

 not common. 



Pisidium pusillum, P. nitidum, and P. Henslowianum (var. pul- 

 chellum). Alexisbad ; not common. 



When we consider that the latitude of the district I have thus 

 cursorily explored is nearly parallel to that of the south-eastern 

 part of Great Britain, it- is curious to observe how many species 

 of Mollusca occur in the former, and not in the latter, region. 

 These exceptions are by no means of species which comprise only 

 a few or inconspicuous individuals, but on the contrary, the 

 individuals are numerous and comparatively large. They are 

 Vitrina diaphana, Helix fruticum, H. incarnata, H. strigella, 

 H. personata, Clausilia plicata, C. plicatula, and C. parvula. 

 One of them (viz. Helix incarnata) occurs as a Pleistocene fossil 



