Little Brown-bat 1155 



more often than its eyes, averts the wreck and ruin that im- 

 petuous flight in gloomy woods might bring. 



It is needful, indeed, that these two fairy gifts should 

 dwell in complement of each other. 



Writing of the wing-membrane, Harrison Allen says:'" 



"It is in this latter structure that the sense of touch 

 chiefly resides. The bones of the extremities being covered on 

 either side with an enduplication of skin, form a framework 

 upon both sides of which the papillae of touch are extensively 

 distributed. This function, in many places, is probably aided 

 by the delicate hairs which are sparsely distributed linearly 

 upon the under surfaces of the membranes. These may per- 

 form a function analogous to that observed in the labial 

 whiskers which are so prominent in the FeliJcc. Spallanzani 

 was the first to notice the high development to which this sense 

 had been brought in these animals. His experiment is well 

 known, but will bear repetition here: 



" 'In 1793, Spallanzani put out the eyes of a Bat, and ob- sense- 

 served that it appeared to fly with as much ease as before, and 

 without striking against objects in its way, following the curve 

 of a ceiling, and avoiding with accuracy everything against 

 which it was expected to strike. Not only were blinded Bats 

 capable of avoiding such objects as parts of a building, but they 

 shunned with equal address the most delicate obstacles, even 

 silken threads stretched in such a manner as to leave just space 

 enough for them to pass with their wings expanded. When 

 these threads were placed closer together, the Bats contracted 

 their wings in order to pass between them without touching. 

 They also passed with the same security between branches of 

 tre&s placed to intercept them, and suspended themselves by 

 the wall, etc., with as much ease as if they could see dis- 

 tinctly.'"" 



Cuvier's explanation (1796) was that during the flight of 

 the blinded Bat, the waves of air set in motion by its wings 

 reacted against their acutely sensitive surface in proportion, 



'" Monog. Bats. N. .\., 1864, pp. xv-xvi. 

 " Godman's Am. Nat. Hist., I, 1826, p. 57. 



