58 WOODLANDERS AND FIELD FOLK 



Our knowledge concerning these birds has much 

 advanced of late years. We know now more ac- 

 curately the lines and the times of migration, and 

 the manner in which this is performed. When in 

 autumn the migratory instinct comes strong upon 

 the hirundines, they do not, as was once supposed, 

 tower straight up, and then start in direct flight for 

 their winter quarters; so that birds which in the 

 morning might be seen hawking for insects over 

 Hyde Park, and the same evening catching flies 

 about the mosques of Jerusalem, are now looked 

 upon by ornithologists as myths. Swallows, like 

 all migratory birds, stick close to land, never leaving 

 it for any distance unless compelled. It is notice- 

 able that they do not cross straits at the narrowest 

 parts, but probably by a route, which dimly in- 

 dicates some long-lost land-line ; that is, they cross 

 now where their ancestors crossed centuries ago. 

 Swallows have alighted upon vessels four hundred 

 miles from land, but from their exhausted state 

 would seem to have been blown out of their course, 

 and to have suffered great fatigue. The food of 

 swallows is taken exclusively from the air, and they 

 drink whilst flying. This, so far as is known, cannot 

 be said of any other bird. Various species of gnats 

 and ephemerae constitute their food upon their 

 arrival in this country, but, as summer advances, 

 winged beetles are also greedily taken. So rapidly 



