CHAP. XVI THE BRITISH ISLES 367 



Many of the above are minute or obscure plants, and 

 are closely allied to other European species with which 

 they may have been confounded. We cannot therefore 

 lay any stress on these individually as being absent from 

 the continent of Europe so much of which is imperfectly 

 explored, though it is probable that several of them are 

 really confined to Britain. But there are a few — indicated 

 by italics — which are in a very different category ; for 

 they belong to genera which are altogether unknown in 

 any other part of Europe, and their nearest allies are to be 

 found in the tropics or in the southern hemisphere. The 

 four non-Euro2Dean genera of mosses to which we refer 

 all have their maximum of develoj^ment in the Andes, 

 while the three non-European Hepatica? appear to have 

 their maximum in the temperate regions of the southern 

 hemisphere. Mr. Mitten has kindly furnished me with 

 the following particulars of the distribution of these 

 genera : — 



Barteamidula. Asia, Africa, S. America and Australia, but not 

 Europe or N. America. 



Stkeptopogox is a comparatively small genus, with seven species in the 

 Andes, one in the Himalayas, and three in the south temperate zone, 

 besides our English species. 



Daltonia is a large genus of inconspicuous mosses, having seventeen 

 species in the Andes, two in Brazil, two in ISIexico, one in the Galapagos, 

 six in India and Ceylon, five in Java, two in Africa, and three in the 

 Antarctic Islands, and one in Ireland. 



HooKERiA (restricting that term to the species referable to Cyclodictyon) 

 is still a large genus of handsome and remarkable mosses, having twenty- 

 six species in the Andes, eleven in Brazil, eight in the Antilles, one in 

 Mexico, two in the Pacific Islands, one in Xew Zealand, one in Java, one 

 in India, and five in Africa — besides our British species, which is found 

 also in Madeira and the Azores but in no part of Europe proper. 



These last two are very remarkable cases of distribu- 

 tion, since Mr. Mitten assures me that the plants are so 

 markedly different from all other mosses that they would 

 scarcely be overlooked in Europe. 



The distribution of the non-European genera of 

 Hepaticae is as follows : — 



Chasmatocolia, South America and Ireland. 



AcEOBOLBUS. A small genus found only in New Zealand and the 

 adjacent islands, besides Ireland. 



