40 ISLAND LIFE 



cannot be far one way or the other from the river Indus as 

 far up as Attock, opposite the mouth of the Cabool river. 

 Here it will bend to the south-east, passing a little south 

 of Cashmeer, and along the southern slopes of the 

 Himalayas into East Thibet and China, at heights varying 

 from 9,000 to 11,000 feet according to soil, aspect, and 

 shelter. It may, perhaps, be defined as extending to the 

 upper belt of forests as far as coniferous trees prevail ; but the 

 temperate and tropical faunas are here so intermingled 

 that to draw any exact parting line is impossible. The 

 two faunas are, however, very distinct. In and above the 

 pine woods there are abundance of warblers of northern 

 genera, with wrens, numerous titmice, and a great variety 

 of buntings, grosbeaks, bullfinches and rosefinches, all more 

 or less nearly allied to the birds of Europe and Northern 

 Asia ; while a little lower down we meet with a host of 

 peculiar birds allied to those of tropical Asia and the Malay 

 Islands, but often of distinct genera. There can be no 

 doubt, therefore, of the existence here of a pretty sharp 

 line of demarkation between the temperate and tropical 

 faunas, though this line will be so irregular, owing to the 

 complex system of valleys and ridges, that in our joresent 

 ignorance of much of the country it cannot be marked in 

 detail on any map. 



Further east in China it is still more difficult to 

 determine the limits of the region, owing to the great 

 intermixture of migrating birds ; tropical forms passing 

 northwards in summer as far as the Amoor river, while the 

 northern forms visit every part of China in winter. From 

 what we know, however, of the distribution of some of the 

 more typical northern and southern species, we are able to 

 fix the limits of the Palsearctic region a little south of 

 Shanghai on the east coast. Several tropical genera come 

 as far north as iNingpo or even Shanghai, but rarely 

 beyond; while in Formosa and Amoy tropical forms 

 predominate. Such decidedly northern forms as bullfinches 

 and hawfinches are found at Shanghai ; hence w^e may 

 commence the boundary line on the coast between Shanghai 

 and Ningpo, but inland it probably bends a little southward, 

 and then northward to the mountains and valleys of West 



