AND ITS DISTRIBUTION. 43 



given by Gmelin and Pallas concerning it. It is only very 

 recently, that, through the excellent investigations of Erman, 

 Baer, and Middendorff, correct views have been gained 

 respecting the extent and thickness of this stratum of sub- 

 terranean ice. Prom the descriptions of Greenland by 

 Crantz, of Spitzbergen by Martens and Phipps, and of the 

 shores of the Sea of Kara by Sujeff, an incautious genera- 

 lisation had represented the whole northern part of Siberia 

 as destitute of vegetation, and with a constantly frozen and 

 snow-covered surface, even in the plains. The extreme limit 

 of the growth of high forest-trees in Northern Asia is not 

 the parallel of 67 latitude, as was long assumed, and as 

 is actually the case near Obdorsk, owing to the influence of 

 sea-winds and the vicinity of the Gulf of Obi. The valley of 

 the great river Lena has lofty trees up to the latitude of 

 71. In the desert islands of New Siberia large herds of 

 reindeer and countless lemmings still find sufficient vegetable 

 sustenance ( 44 ). The two Siberian journeys of Middendorff, 

 a traveller eminent for the spirit of observation as well as for 

 boldness of enterprise and perseverance in laborious re- 

 search, were made from 1843 to 1846, and were directed 

 northwards, into the Taymir country, to nearly 76 N. lat. ; 

 and to the south-east as far as the upper Amour and the 

 Sea of Ochozk. The first of these adventurous journeys led 

 the learned traveller into a previously wholly unvisited region, 

 the more important and interesting because situated at an 

 equal distance from the east and west coasts of the old 

 continent. The instructions of the Petersburg Academy 

 of Sciences, commended to him as a leading object of his 

 expedition (in canjunction with the limits of the various 

 forms of organic life towards the high north, depending 



