ECOLOGICAL 79 



at a smart walking pace, unless the wintry conditions set in very 

 abruptly. The reindeer travel for the most part by day, along more 

 or less well-trodden paths, in relatively small companies, and in 

 single file. Of interest is the fact that the earlier companies consist 

 mainly of does, fawns, and young stags, while the later companies 

 consist mainly of the big stags. In the spring there is a return move- 

 ment, when the does are heavy with young, which is somewhat 

 divergent from the avian migration scheme. Too much must not 

 be made of this difference, yet it must be admitted that the so-called 

 reindeer "migration" approximates to the mass- movements of gre- 

 garious Ungulates of steppe-like areas when the dry season compels 

 them to "follow the grass". Moreover, some Caribous are practically 

 resident both in the northern and the southern parts of Newfound- 

 land. On a somewhat similar betwixt-and-between level are the 

 seasonal movements of Rhesus and Hanuman monkeys in India. 

 They move in the hot season from the plains to the hills of Nepal, 

 and return to the low grounds in the cold season, bringing their 

 young with them. There is no doubt that some of the bats take 

 gregarious flights on a large scale, while others may pass in crowds 

 every evening from the mainland to an adjacent island, just as 

 starhngs are known to do. But it is very doubtful whether any of 

 the mass-movements of bats can be included within the rubric of 

 migration. Willey refers to an interesting "Box and Cox" alternation 

 in Ceylon, where certain fruit-eating bats rest among the palms of 

 an adjacent islet during the day, but go to the main island to feed 

 at night, while flocks of crows alternate with them by roosting on 

 the islet palms by night and visiting Ceylon by day. But nothing 

 is gained by calling this migration ! 



Reptiles. — Some of the marine turtles are good instances of true 

 migrants. Thus the Loggerhead (Caretta caretta), a carnivorous species 

 of tropical and intertropical seas, visits many sandy shores to 

 deposit the eggs on the beach. The newly hatched young ones make 

 persistently for the sea, moved, as G. H. Parker has experimentally 

 shown, by a constitutional obligation to go down a slope and to 

 walk in the direction of the most open low horizon, be this the right 

 way to the sea or no. The vegetarian Green Turtle [Chelone midas), 

 which deposits its eggs on sandy beaches in the West Indies, has a 

 short migrational range, not known to exceed 50 miles. It spends 

 ten months of the year in the relatively shallow coastal waters, for 

 though it is sometimes found in the open ocean, its normal haunt is 

 bound to be not very far from the seaweed- growing region. Some 

 of the sea-snakes are true migrants, for they come periodically to 

 the shore to give birth to their young ones among the rocks. 



Amphibians. — A famihar sight in spring in some places is the 

 march of toads from a considerable distance to a particular pond 

 or marsh, where they pair and spawn. When, some months later, 



