Instinct and its Lessons 127 



obstacle, swimming lakes and climbing houses which 

 lie in their path. They winter beneath several feet 

 of snow, and rear families on their journey. All 

 the way along they are accompanied by another crowd 

 of travellers for whose movements their migration 

 is the signal. The Fox, the Stoat, and the Hawk 

 find a ready livelihood provided for them in the ranks 

 of the caravan; the Great Snowy Owl is on these 

 occasions alone to be found in its best condition : 

 even such pacific animals as Reindeer and Goats 

 develop ferocity in presence of the Lemming, stamp- 

 ing them to death, and, according to some authorities, 

 actually devouring them. All this makes it hard 

 enough to understand what benefit this migration 

 brings to the migrants, but it is all as nothing with 

 the final issue. Steering ever due west the Lemmings 

 arrive at last at the shore of the Atlantic. This 

 obstacle they treat like all the others. On the first 

 calm day they plunge into the sea and the whole 

 multitude perishes to its last member, the front of 

 the host still pointing to the west. As Mr. Romanes 

 tells us, 1 "No faint heart lingers on the way, and 

 no survivor returns to the mountains." So vast are 

 the number thus immolated, that in November, 1868, 

 a ship sailed for fifteen hours through a swarm of 

 swimming Lemmings. To explain this instinct has 

 baffled, as well it might, the ingenuity even of theory. 

 Mr. Wallace suggests that Natural Selection has played 

 an important part in causing migration, by giving an 

 advantage to those animals, which enlarge their 

 breeding area by travel. Mr. Crotch, however, per- 

 tinently remarks that, "if none return or survive, 

 it is difficult to say what becomes of the fittest." 

 Having disposed of Mr. Wallace's explanation, Mr. 

 Crotch proceeds to give his own, which is even more * 

 remarkable. He finds in the instinct of the Lemming / 

 an argument for the existence of the island of Atlantis, J 

 that vague and shadowy land spoken of by Plato 

 1 Mental Evohition in Animals, p. 283. 



