B. F. CUIVI MINGS : BIRD ROOSTS AND ROUTES. 123 



came accurately along a mathematically straight line, as 

 far as x. 



On February 19th I was at this spot watching the 

 Starlings. I was particularly interested in one flock 

 which never arrived along the usual, main, flight-line, 

 but cut into it at right angles (as indicated in the sketch 

 map). This flock, on this particular evening, however, 

 appeared to have lost its bearings, for it wandered about, 

 as I show in the sketch, as if trying to cross Coddon Hill, 

 which the birds never did at any time ; flnally, it seemed 

 to perceive its whereabouts, doubled back and went on, 

 crossing the 400-foot ridge. On the 22nd, this same 

 flock was making for the roost, flying against a heavy 

 westerly gale. Hard weather and frost seems to make 

 no diminution in numbers at the roosts. I may mention 

 here that on every occasion that I have visited a Starling 

 roost last winter (about seven times) there was always 

 a Sparrow-Hawk flying close at hand, and I have repeat- 

 edly seen this Hawk harrying flocks as they came in to 

 roost. 



Individual flocks, when perhaps three miles away from 

 their roost, and out of the main stream of " migration," 

 followed, I found, in the few cases I had under ob- 

 servation, the same route every night. One small flock, 

 for example, always crossed the River Taw at a certain 

 point near a signal box, for several weeks last winter. 

 Routes, however, like these, on the extreme periphery 

 of the system, vary when the particular flock changes 

 its feeding quarters. 



Possibly some of the foregoing will have to be modifled 

 after more prolonged observation, but the main point 

 will hold — the universal use of flight-lines by Starlings in 

 going to and from their roost. 



Whether birds, with their large semi-circular canals, 

 have a sense of direction or whether their migrations are 

 carried out by the aid of the sun or by the earth's 

 magnetism or any other power is moot, yet one thing 

 seems certain and that is that they possess a powerful 



