94 MAMMALIA ORDER V.RODENTIA. 



allied to the Cabul species to be immediately mentioned. The Deosai 

 plateau, it may be mentioned, is one of the most desolate and dreary regions 

 that can well be imagined, consisting of rolling hills and dunes of sand and 

 gravel, with a sparse coating of vegetation, where almost the only living 

 things to be seen are marmots and mosquitoes. The climate is most 

 rigorous ; the sun's rays beating down with terrific power through the dry 

 and rarified atmosphere during the day in the summer months, but the tem- 

 perature rapidly falling, and often sinking below the freezing point after 

 sunset. In winter this region is absolutely impassable ; so that its climate 

 may be regarded as an intensification of that of the steppes. 



The Cabul marmot. ( A. dichrous), which is also met with in Turkestan, is a 

 smaller species than the golden marmot, from which it is further distinguished 

 by its duller coloration, and the absence of any black on the back. The 

 regions whence it is obtained have a climate of the general character men- 

 tioned above. The last species to be mentioned is known as the red or long- 

 tailed marmot (A. caudatus). This appears to be the largest of all those 

 found in the Old World, attaining a length of nearly two feet, exclusive of 

 the tail, which measures about one foot. It is readily recognised, not only 

 by its size and long, bushy tail, but also by the full rufous tinge of the hair, 

 and the large extent of black found on the back of many individuals, the 

 skins being handsomer than those of any of the other kinds. 



The distribution of this Himalayan marmot is extremely interesting as 

 showing that these animals can only exist in an arid climate more or less 

 nearly approaching that of the steppes or of Tibet. To understand this, it 

 must be mentioned that the immense mountain-barrier lying to the north- 

 ward of the valley of Kashmir, the lowest gap in which has an elevation of 

 11,500 feet, cuts off almost completely the clouds coming up from the plains 

 of India from the more or less arid regions to the northward. Now, whereas 

 marmots are totally unknown on the great range of mountains south of the 

 Kashmir valley, where the rainfall is excessive, directly the traveller reaches 

 the summits of the passes of the northern range, and thence far down on the 

 northern side, the shrill cry of the red marmot strikes his ear. This is very 

 noticeable in travelling on the Central Asian high road up the Sind Valley, 

 when he crosses the Zogi Pass into the Tibetan area. This marmot may like- 

 wise be met with on crossing the passes leading to our distant frontier 

 station of Gilgit ; and it also appears to range into many parts of Ladak, 

 although its exact limits are not yet accurately defined. It is thus evident 

 that marmots now exist only at such elevations or in such regions as possess 

 an extreme continental climate that is to say, one where the summers are 

 hot and the winters excessively cold. It has been shown that in Europe the 

 Alpine marmot inhabits three distinct and isolated ranges, separated from 

 one another by low-lying areas possessing a climate entirely different from 

 the type above referred to ; and it is thus clear that it could not have crossed 

 these unsuitable low areas while the climate of Europe was the same as at 

 the present day. That there must have been at some time or other a direct 

 communication between these isolated marmot areas is, therefore, self- 

 evident. 



The next section of the Sciuridce is formed by the true, or northern flying 

 squirrels, of which there are three well-marked generic groups. In all these 

 animals the parachute is supported by a rod of cartilage projecting like a 

 yard-arm from the outer side of the wrist, and there is another expansion of 

 skin connecting the fore-limbs with the neck, while there may be a third 



