62 Wild Birds and their Haunts 



writer had. occasion to send a dog by train on a long 

 journey, at trie end of which, however, he managed to 

 escape, reappearing a few days after in a very emaciated 

 condition, having scampered the sixty or more miles 

 without food till the homestead was reached. Another 

 instance, a pet dachshund, about a year old, was put into a 

 sack on the estate of its owner, and conveyed in a close 

 cart to a farm miles away. Arrived at its destination, the 

 dog was liberated, but disappeared, and was back home 

 again before the conveyance returned ! Some farm hands 

 stated that the animal was seen going " as the crow 

 flies " across ditches and through hedges in a direct line 

 for home. 



On the trackless plains of North America cattle, after 

 having been driven for hundreds of miles, have followed 

 the same method of returning, oft-times through brush- 

 wood and dense forests. 



So far, mention has been made of the land routes of the 

 migratory species. It is now my intention to bring under 

 the reader's notice a theory which has been established to 

 explain the crossing of wide seas by this host, more 

 especially in relation to the occurrence of American birds 

 in Europe. 



As already intimated, it was considered absolutely 

 impossible for a bird to traverse a stretch of water at least 

 sixteen hundred miles in breadth, which is the extent of 

 the Atlantic between Newfoundland and Ireland. Hence 

 it was believed that the only way in which it could accom- 

 plish this journey was by making use of what was called 

 M diluvial land bridges." These at the present day are 

 represented by the mere isolated remnants of what, in 

 primary geological periods, were large land connections 

 between different continents. 



In the case of birds crossing over from America to 

 Europe, such a connection is assumed to be formed by 

 Greenland, Iceland, the Faroes, Shetland and Orkney 

 Islands. The employment of this path as a migration 

 route is considered to have developed into a habit, and 

 this habit to have passed by hereditary transmission from 

 one generation to another from primitive times down to 



