98 



FLORA INDICA 



shrubs, etc., amongst it. This vegetation presents many pecu- 

 liar features, and its total absence from the plains is not to be 

 accounted for by any simple law of climate. Amongst other 

 Orders we may mention especially Magnoliacea, Ternstrce- 

 miacea, subtropical Rosacea (as, Prunus, Photinia, etc.), Kad- 

 sura, Sphtsrostema, Rhododendron, Vaccinium, Ilex, Styraw, 

 Symplocos, Olea, Sapotaceae, Lauracece, Podocarpus, Pirns lon- 

 gifolia ; with many mountain forms of truly tropical families, 

 as Palms, Pandanits, Musa> Clusiacece, Vines, Vernonia, and 

 hosts of others. These are instances of more or less strictly 

 mountain plants prevailing uniformly over many degrees of 

 latitude and longitude without ascending or descending much, 

 but which are so rarely seen on the plains, as to entitle them 

 collectively to a separate notice when treating of the phases of 

 Indian vegetation. 



Advancing westward, especially in the Himalaya, we expe- 

 rience a drier climate, which exaggerates the effect of eleva- 

 tion on the vegetation, and produces besides many curious 

 anomalies, as a reduced mean temperature divided into two 

 seasons, one of heat and one of cold, which are more con- 

 trasted at these elevations than on the plains. It is ob- 

 viously impossible to enter here into the details of the ap- 

 parent anomalies thus caused in the distribution of plants ; 

 each individual species demanding a study of its natural habits 

 to explain its aptitude for an extended distribution in eleva- 

 tion, or geographical position, or its absolute restriction to a 

 very narrow area, or to a few spots characterized by a combi- 

 nation of favourable circumstances. Examples may be seen 

 in the Ephedra of the Panjab and north-western Himalaya, 

 which ranges from the plains to 16,000 feet; in the genus 

 Marlea, which ascends from 3000 to 8000 feet in Sikkim, 

 and in the western Panjab, at scarcely 4000 feet, accompanies 

 Celtis and a species of Ash j in a subtropical Myrsine, which 

 extends even into Afghanistan ; in Juniperus excelsa, found as 

 low as 5000 feet in Afghanistan, and which ascends to 15,000 

 in Tibet. 



