CHIROPTERA 41 



possess a marvellous faculty for finding their way about under 

 conditions which would render human beings helpless. A 

 good illustration of this power is described by Professor C. 

 Lloyd Morgan,^ quoting Miss Caroline Bolton, who was present 

 during an experiment in which threads were fastened crossing 

 each other in all directions at intervals of about sixteen inches 

 in a room measuring twenty feet by sixteen. To each 

 thread a bell was attached in such a way that the slightest 

 touch would make it ring. Into this room a large bat was 

 liberated in absolute darkness, but, although the observers could 

 hear the animal flying about for half an hour no bell was rung. 

 So keen are their perceptions that, unlike birds, bats usually 

 perceive windows,^ and if they fly against them, it is not with 

 the blind dash of a bird. It has been noticed of a Lesser 

 Horseshoe that it persistently flew at a large mirror, "and 

 though it never actually touched it, it hovered in front of it in 

 such a way as to indicate clearly that it was in some way 

 deceived by it." 



All authorities are agreed that bats are in no apparent way 

 incommoded by the partial destruction of their eyes ; but, as 

 regards the loss of power consequent upon the loss of other 

 organs, the older writers differed somewhat, and it seems quite 

 possible that the mere shock or pain caused by the operations 

 of the experimenters may have in some cases interfered with 

 the victim's movements. The element of disagreement is parti- 

 ally lessened and explained by more recent investigators,^ who, 

 after an examination of several species, conclude that the power 

 which enables bats to move with certainty in the most complete 

 obscurity, is not absolutely located in any single organ, but 

 arises from a combination of senses resulting from several 

 organs acting in unison and mutually assisting each other. 

 The most important of these, in the order named, are : (i) hear- 

 ing, or rather, as Mr Hahn puts it, a sense or senses located 

 in the internal ear ; (2) touch, specially distributed in the naked 



' Animal Life and Intelligence, 1890-91, 247. 



2 Not always— see G. H. Caton Haigh on Daubenton's Bat, Zoologist, 1889, 434 ; 

 also Osburn ; and Hahn, whose experiments led him to regard the ordinary esti- 

 mates of a bat's skill in avoiding obstacles as exaggerated {pp. cit., supra, vide p. 3). 



3 Messrs Rollinat and Trouessart, Comptes rendus Soc. Biol., Paris, 23rd June 

 1904, 1-4 (reprint). 



F 



