THE ARCTIC LEMMING 195 



increase of numbers which occasions their wonderful exodus from the 

 high plateaus and descent into the cultivated lands, which may happen 

 at either short or long intervals; as few as five, and as many as 

 twenty years, may elapse between " Lemming years." When once 

 started on their pilgrimage, nothing stops the brave little creatures ; 

 they climb hills, enter towns, and fearlessly cross rivers and even 

 lakes, for they can swim for miles, though, of course, in a long water- 

 passage many perish. Finding more to eat than they ever got at 

 home, and not travelling continually, but often settling for a time, 

 they breed more freely than before, but still move slowly on. All 

 carnivorous creatures, furred and feathered, live luxuriously upon them, 

 and disease makes havoc among the crowd, but still they slowly press 

 onward, till at the end they reach the sea. Not knowing the extent of 

 this new watery obstacle, the survivors boldly set out to swim across it, 

 and with their death by exhaustion and drowning the expedition ends. 

 One cannot help feeling touched at such a fate for the gallant little 

 Vikings ; but it comes as a relief to their human neighbours, for they 

 are naturally almost as destructive as locusts in many places. Lemmings 

 are not often to be met with in captivity, but I have seen a few both 

 in the London Zoological Gardens and at Mr. Hamlyn's, and their habits 

 would be well worth studying if they were kept as pets. 



THE ARCTIC LEMMING 



(Cunuu/ns torquatus) 



ANOTHER species of Lemming (Myodes obensis), closely allied to the 

 Scandinavian one, is found in Northern Siberia and North America, 

 but the characteristic Arctic Lemming is a very distinct species, even 

 more chubby in form than the ordinary kinds, with no external ears, 

 and hardly any tail. Moreover, the feet are different, the first toe of 

 the fore-paws being quite rudimentary, while the third and fourth 

 bear very large and strong claws, which receive an extra growth of 

 horny matter in winter. At this season also, the coat, which is much 

 greyer in summer than that of ordinary Lemmings, turns pure white. 

 This little creature is active under the snow in the winter, and inhabits 

 even Novaia Zembla, as well as Greenland. 



