144 



REPORT — 1839. 



• The distribution of the Aquatic Pulmonifera is much more 

 equal than that of the Terrestrial, as might be expected from 

 the nature of the element in which they live. In Limneus, 

 Planorbis, Physa, and Ancylus, the differences between the 

 European lists are very slight, and the species are generally 

 identical. The himneus involutus of Harvey would appear to 

 be the only species peculiar to Britain, not having been found 

 elsewhere than in its Irish locality. Some of our native spe- 

 cies have very wide ranges, Limneus stagnalis extending from 

 Cachemyr to the United States, and Limneus palustris occur- 

 ring in most parts of the world. Limneus per eg er is also very 

 widely distributed. Limneus minutus is found in very elevated 

 situations in the Alps, and in low ground in the north of 

 Africa. The genera Limneus, Physa, and Planorbis, are 

 found to inhabit most parts of the world. 



Table 

 Of the Species of Pulmoniferous Mollusca inhabiting the Bri- 

 tish Isles, and their Geographical Distribution. 





Genera and Species. 



British Distribution. 



General Distribution. 



I. 



LiMAX, Linn. 



[Arion.] 







1 



Empiricorum, Fer. 



I.-X. 



All Europe, Teneriffe. 



2 



hortensis, Fer. 



[LiMAX.] 



11.— vin. 



Central& Northern Europe. 



3 



cinereus, Linn. 



I.— X. 



Europe, Teneriffe, Algiers. 



4 



variegatus, Fer. 



II. 



Europe, Cyprus, U. States. 



5 



agrestis, Linn. 



I.— VIII. 



All Europe, Teneriffe. 



6 



Sowerbii, Fer. 



II.. VII. 



France. 



7 



brunneus, Drap. 



VIIL 



France. 



II. 



Testacellus, Cuv. 







1 



haliotoideus, Drap. 



L— in., VII. 



S. W. of Europe. 



H 



scutulum, Sow. 



II., VII. 





III. 



ViTRiNA, Drap. 







1 



pellucida, Miill. 



I.— X. 



N.& C.Europe, Greenland. 



U 



Drapernaldi, Jeff. 







Diapliana, Jeff. 







Dilwynii, Jeff. 







IV. 



SucciNEA, Drap. 







1 



amphibia, Drap. 



I.— IX. 



All Europe, N. America, 



i§ 



gracilis, Alder. 

 (Pfeifferi), Rossm. 





Africa, Western Asia. 



2 



oblonga, Drap, 



III., VIIL 



N.& C. Europe, S. America, 

 Cape of Good Hope. 



V. 



Helix, Linn. 







1 



pomatia, Linn. 



II., IIL, ? 



C. & S. Europe, W. Asia, 

 N. Africa, S. America. 



2 



arbustorum, Linn. 



II.— IX. 



N. E. and C. Europe. 



3 



aspersa, Mull. 



I.-IX. 



C.& S. Europe, Asia, Afri- 

 ca, N. & S. America. 



