LIFE ON THE EASTERN ISLES 211 



settling down to breed irregularly in different 

 spots, being guided apparently by the abundance of 

 the locusts, which form a favourite food. 



In the East Indies there are curious cases of 

 inter-insular migration in at least two Pigeons, the 

 ground-feeding Nicobar or Hackled Pigeon (Calcenas 

 nicobarica) and the arboreal Pied Fruit-Pigeon 

 (MyristicWora luctuosa), which wander far and wide 

 in the many islands of the Indian Ocean, but 

 do not come to the mainland. The case of the 

 Nicobar Pigeon is particularly remarkable, as only 

 scattered pairs are found breeding elsewhere than 

 on Batty Malve, a small and fortunately very 

 inaccessible islet in the Nicobar group, which 

 appears to be a perfect Pigeon-house during the 

 season when the birds rear their single chick. 



This regular return to isolated spots in huge 

 numbers is almost unique in a land-bird, but, as is 

 well known, quite a common thing among sea- fowl, 

 especially Petrels and Penguins ; it was only com- 

 paratively recently found out where one of the com- 

 monest and most widespread among southern ocean 

 Petrels, the well-known spotted " Cape Pigeon " 

 (Daption capensis), nested, the locaUty being Ker- 

 guelen. Wilson's Petrel {Oceanites oceanicus) also 

 nests in Kerguelen, and spends the southern winter 

 in the north, affording a rare instance of a southern- 

 breeding bird crossing the equator, though it is 

 quite the usual thing for migrants from north to 

 south to go far south of this line. 



It has, indeed, been found that of migratory 



