68 VESPERTILIONID.E— NYCTALUS 



required to assist in retaining it until masticated.^ Proof 

 of this contention is, however, not forthcoming, and it is note- 

 worthy that Mr Oldham, who has spent hours watching Noctules 

 under favourable conditions, both with the naked eye and with 

 a strong glass, has never detected them using the thumb to 

 rend asunder their prey. It seems clear, from the evidence of 

 Messrs Coward, H. E. Forrest, J. G. Millais, and Oldham, 

 that the plunge takes place obliquely downwards, both wings 

 being clearly extended— a posture very different from a vertical 

 fall, such as occurs when there is a loss of balance, as when 

 one wing is broken by shot. My own conclusions are 

 thoroughly in accord with the opinion" that the plunge is 

 made after insects below and off the direct line of flight. The 

 fact that it may take place not only downwards, but in an 

 oblique direction, is indeed an almost proof positive of its 

 objective. It is a falcon-like swoop, the tremendous force 

 of which is illustrated by Mr Whitaker's ^ experience of a bat 

 which, in pursuit of a pebble, struck a butterfly-net so violently 

 as to break a wing and nearly dash the net from his hand. 



Sometimes, however, food is not so readily obtained. With 

 a cold east wind, or indeed a strong wind from any quarter, 

 a change of hunting ground is required, and the Noctule may 

 then be seen taking a humble and silent flight in some 

 sheltered corner, fluttering about with half-closed wings, and 

 appearing to be very little at home or, indeed, like itself; for 

 instances are on record where several have been shot under the 

 belief that they were of some unknown species. 



Long ago Wolley graphically described * its flight as always 

 strong, but varying " remarkably at different times, no doubt 

 influenced, like that of the swallow, by the casual range of its 

 prey ; at one time it may be seen flying away, straight and 

 swift, at a great height in the air, no more to appear that 

 evening ; at another it will be performing a great circle, return- 

 ing perhaps once in five or ten minutes ; or it may be flying 

 low (and then I think silently) along the streets of a town: 

 again it is wheeling round tall elms, in company with others 



^ See, for instance, Oxley Grabham, Zoologist, 1899, 131. 



2 Trans. Caradoc and Severn Valley Field Club, 1900 (Feb. 1901), 243. 



3 In MSS. * Zoologist, 1845, 953. 



