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THE NATIONAI. GEOGRAPHIC MAGAZINE 



those stern northern wilds. To the southward 

 they extend into the subarctic northern for- 

 ests, where they usually keep to the open bar- 

 ren areas. 



Not much is known of their life histories on 

 this continent. They are mainly nocturnal and 

 live in burrows from two to three feet long, 

 ending with a nest chamber four or five inches 

 in diameter, warmly lined with grass and moss. 

 Near the nest there is usually a branch burrow 

 a foot or more long which is used for sanitary 

 purposes and as a place of refuge when the 

 main burrow is invaded. 



In the nests during early summer litters gen- 

 erally containing about three young are brought 

 forth. Ordinarily the burrows open in unshel- 

 tered places, but in wooded regions may be 

 under a log or beneath a bush or the roots of 

 a tree. No runways lead out from the bur- 

 rows as is customary with many of their rela- 

 tives. They are active throughout the winter, 

 making many tunnels along the surface of the 

 ground under the snow, which are revealed 

 when it melts in spring. 



These surface tunnels are their foraging 

 roads, safe from most of the fierce storms 

 which rage overhead. At times, however, the 

 snowy shelter is blown away or some other 

 cause brings the lemmings to the surface, where 

 they blunder aimlessly about, soon to be cap- 

 tured by some enemy or to perish from the 

 cold. As their infrequent appearance on top 

 of the snow is usually during storms, the 

 Alaskan Eskimos have a legend that these 

 white lemmings live in the land above the stars 

 and descend in a spiral course to the earth 

 during snowstorms. 



Although banded lemmings never become so 

 extraordinarily numerous over great areas as 

 the brown species, they become very abundant 

 at times in the barren grounds of Canada and 

 the Arctic islands and migrate from one part 

 of their range to another. The best observa- 

 tion in regard to this was made by Rae in June 

 at the mouth of the Coppermine River. On 

 the west bank of the river north of the Arctic 

 Circle he encountered thousands of them speed- 

 ing northward. 



The ice on some of the smaller streams had 

 broken up and he was amused to see the little 

 animals running back and forth along the banks 

 looking for a smooth place in the stream, indi- 

 cating a slow current, where they could swim 

 across. Having found such a place, tlicy at 

 once jumped in and swam quickly to the oppo- 

 site side, where they climbed out and, after 

 shaking themselves like dogs, continued their 

 journey as though nothing had happened. 



During the years I lived in northern Alaska 

 the advent of winter was marked by invasion 

 of the storehouses by many brown lemmings 

 and other mice, but banded lemmings rarely 

 appeared. When occasionally captured alive, 

 the old ones fought viciously, but the young 

 were gentle and quickly became tame and in- 

 teresting pets. Their skins were highly prized 

 by the little Eskimo girls to make garments 

 and robes for ihcir walrus ivorv dolls. 



THE BROWN LEMMING (Lemmus 

 alascensis and its relatives) 



{For illustration, see page ^ig) 



Eew small mammals are so well known in 

 far northern lands as the brown lemmings. 

 They form a small group of species having a 

 close general resemblance to some of the field 

 mice, from which, however, they may at once 

 be distinguished by their much heavier propor- 

 tions, extremely short tails, and the remarkable 

 length of the hair on their backs and rumps. 



They inhabit most of the arctic and subarctic 

 lands of both Old and New Worlds. In North 

 America they are known from the northern- 

 most lands, beyond 83° north latitude, to the 

 southern end of Hudson Bay, and throughout 

 most of northern Canada and all of Alaska, 

 including the islands of Bering Sea. 



The extraordinary migrations of these lem- 

 mings have attracted attention far back in the 

 early history of northern Europe. At inter- 

 vals, through favorable conditions, they become 

 superabundant over a large area, and then a 

 sudden resistless desire to migrate in a certain 

 direction appears to seize the entire lemming 

 population. The little beasts start in a swarm- 

 ing horde, sometimes containing millions, and 

 traverse the country. 



In their travels they appear indifferent to all 

 obstacles and with dogged and unwavering per- 

 sistence swim the streams and lakes encoun- 

 tered on their way. Similar migrations have 

 been observed at various points in Arctic 

 America, several of them in Alaska, where the 

 lemmings abound on the open tundras. 



These migrations sometimes continue for 

 more than one season, the animals meanwhile 

 being killed in countless numbers by disease, 

 by accident in field and flood, and, in addition, 

 through the heavy toll taken from their num- 

 bers by their winged and four-footed foes, 

 which always gather in numbers to accompany 

 them. 



The migrations sometimes wear out through 

 the diminution in numbers, and sometimes 

 when they reach the sea, as in Norway, they 

 are said to enter the water and swim offshore 

 until they perish. When one of these swarms 

 of rodents passes through a farming district it 

 cleans up the crops and other surface vegeta- 

 tion like a visitation of locusts. 



These lemmings do not hibernate, but, active 

 throughout the severest winters, are abroad 

 almost equally by day and by night. Their 

 burrows consist of winding tunnels, often 

 many-branched and with more than one open- 

 ing. A dry bed of peat or a dense growtli of 

 moss is often pierced by a network of them. 

 Well-defined runways often lead away from 

 the burrows or from the entrance of one bur- 

 row to that of another. 



Their tunnels run everywhere under the 

 snow, with occasional passages leading to the 

 surface. When fierce gales blow away the 

 snow or a winter rain melts it, many lemmings 

 lose touch with their burrows and wander 

 about until they perish from cold or are caught 



