108 FLOEA INDICA. 



upon the fact that not only are a large proportion of annual 

 and herbaceous species of each common to Western India 

 and Europe, but of shrubs and trees also. 



Although the progress we have hitherto been able to make in 

 critically examining our own Indian collections is very limited, 

 we have already established the identity of so many Himalayan 

 plants with European ones, as to oblige us to look to a com- 

 mon origin for the species found in both these regions, and 

 to seek for causes no longer in operation to account for their 

 distribution over so extended an area. The mormtain mass of 

 Asia, as is well known, sinks to the westward of Afghanistan, 

 rising again only in isolated peaks ; and hence the Himalaya 

 is rather ideally than really connected with the moimtains 

 south of the Caspian, and so with the Caucasian Alps on one 

 hand, and those of Asia Minor on the other ; nevertheless we 

 find a multitude of mountain plants, and indeed many of the 

 most conspicuous ones of Eiu'ope, ranging from the coasts of 

 the Levant and the Black Sea to the Himalaya. Of these, 

 again, some are confined within these limits, as Corylus Co- 

 lurna (C lacera, Wall.) ; others spread no further east than 

 the North-western Himalaya, but continue westward to the 

 south of Spain, as Quercus Ilex, Ulmus campestris , Celtis 

 australis and orientalis ; and others, again, advance eastward, 

 spreading over the whole Himalaya, as the Walnut, Ivy, 

 Juniper, and Yew, some of which extend into the Khasia; 

 and two, Juniper and Yew, spread yet further across China, 

 Mexico, and throughout North America. These European 

 forms are almost confined to the temperate regions of India, 

 and with them we also find abundantly the herbs and shrubs 

 of Northern Europe, inhabiting a loftier level in the Himalaya, 

 where they blend with the Siberian types. We cannot con- 

 ceive anytliing more valuable or suggestive to the student of 

 geographical distribution than an accurate list of these Euro- 

 pean plants, which may be grouped under three heads : — 1 . 

 Such as are common to most parts of Europe, Northern Asia, 

 and North America, and the Himalaya, such as the Yew, 



