132 



i:\Ti;iaNGS at the MicRoscorK. 



a minute fleslij bulb. Tliose from tlie areas near and 

 at the margins of the palms more and more arch out- 

 wards, so that the space covered bj the bulbs of the 

 filaments is considerably greater than that of the 

 palm itself. 



Kow it is evident that the bulbous extremities of 

 these soft filaments are the organs of adhesion. AYe 

 notice liow thej drag and hold, as the flj draws its foot 

 from its place, and it seems almost certain that the ad- 

 liesion is eifected by means of a glutinous secretion 

 poured out in minute quantities from these fleshy tips. 

 When the foot is suddeulj removed, we maj often see 

 a number of tiny particles of fluid left on the glass where 



the filaments had been in con- 

 tact with it : but I do not 

 build conclusively on this ap- 

 pearance, because the fly, 

 having been confined for 

 some quarter of an hour in 

 this nearly tight glass cell, 

 has doubtless exhaled some 

 moisture, which has condens- 

 ed on the glass ; and the species 

 we see may possibly be due 

 to the filaments of the palms 

 having become wet by repeat- 

 edly brushing the moist sur- 

 face. Mr. Ilepworth, how- 

 ever, asserts that a fluid is 

 poured out from these fila- 

 ments, and is deposited on 

 tlie glass, when the fly is vigorous, with great regularity, 

 lie says that " when in a partially dormant state, the 



FOOT OF FLY. 



