IX.] THE NEW SIBERIAN ISLANDS. 311 



ought not to be overlooked that in sheltered places overflowed 

 by the spring inundations there are found, still far north of the 

 limit of trees, luxuriant bushy thickets, whose newly-expanded 

 juicy leaves, burned up by no tropical sun, perhaps form a 

 special luxury for grass-eating anin^als, and that even the Ueakcst 

 stretches of land in the high north are fertile in comparison with 

 many regions where at least the camel can find nourishment, for 

 instance the east coast of the Bed Sea. 



The nearer we come to the coast of the Polar Sea, the more 

 C(jmmon are the remains of the mammoth, especially at places 

 where there have been great landslips at the river banks when 

 the ice breaks up in spring. Nowhere, however, are they found 

 in such numbers as on the New Siberian Islands. Here Heden- 

 stroni in the space of a verst saw ten tusks sticking out of the 

 ground, and from a single sandbank on the west side of Liach- 

 off's Island the ivory collectors had, when this traveller visited 

 the spot, for eighty years made their best tusk harvest. That 

 new finds may be made there year by year depends on the bones 

 and tusks being washed by the waves out of the sandbeds on 

 the shore, so that after an east wind which has lasted some time 

 they may be collected at low water on the banks then laid 

 dry. The tusks which are found on the coast of the Polar 

 Sea are said to be smaller than those that are found farther 

 south, a circumstance which j)ossibIy may be explained by 

 supposing that, while the mammoth wandered about on the 

 plains of Siberia, animals of ditferent ages pastured in com- 

 pany, and that the younger of them, as being more agile and 

 perhaps more troubled by flies than the older, went farther 

 north than these. 



Along with bones of the mammoth there are found on the 

 New Siberian Islands, in not inconsiderable numbers, portions of 

 the skeletons of other animal fornjs, little known, but naturally 

 of immense importance for ascertaining the vertebrate fauna 

 which lived at the same time with the mammoth on the plains 

 of Siberia, and the New Siberian group of islands is not less 

 remarkable for the "wood-hills," highly enigmatical as to their 

 mode of formation, which Hedenstrom found on the south coast 

 of the northernmost island. These hills are sixty-four metres 

 high, and consist of thick horizontal sandstone beds alternating 

 with strata of fissile bituminous tree stems, heaped on each 

 other to the top of the hill. In the lower part of the hill the 

 tree stems lie horizontally, but in the upper strata they stand 

 upright, though jDerhaps not rootfast.^ The flora and fauna of 

 the island group besides are still completely unknown, and the 

 fossils, among them ammonites with exc|uisite pearly lustre, 



^ Hedenstrijin, loc. c'lt. p. 128. To find stranded driftwood in an upriglit 

 position is nothing uncommon. 



