( 6 9 z ) 
veral Flies, I thought fit to tranfcribe what Dr. Hook fays 
concerning the fame in his Micrographia, and to give the 
Figure thereof, as it is by him delcribed. See Lit. £, in 
regard the Book is very fcarce, Micrographia, Obferv. 38. 
pag. 173. 'WhilftI was examining and confidtring the 
' curious Mechanifm of the Wings, I obferved that un- 
* der the Wings of mod kinds ot Flies, Bees, ©V. there 
i were placed certain Pendulums, or extended drops (as 
4 I may call them from their refembling Motion and f i- 
* gure) for they much refembled a long hanging drop of 
4 lome tranfparent vifcous Liquor ; and I obierved them 
4 conftantJy to move juft before the Wings of the Fly be- 
' gan to move; fb that at the firft fight I could not but 
* guefs, that there was fome excellent ufe as to the Re- 
4 gulation of the Motion of the Wings, and did fancy that 
4 it might be (bmething like the Handle of a Cock, which 
4 by vibrating to and tro, might as 'twere open and (hut 
4 the Cock, and thereby give a paffageto the determinate 
4 Influences into theMuicles : After wards, upon fome o- 
' ther Trials, Ifuppofed that they might be for fome ufe 
4 in Refpiration, which for many Reafons I fuppofe thofe 
4 Animals to ufe ; and methoughtit was not very impro- 
' bable, but that they might have convenient paflages un- 
4 der theWingsfor the emitting (at !eaft)of the Air, if not 
' admitting, as in the Gills of Fifties is moft evident.Orper- 
* haps this Pendulum might be fomewhat like the Staff to 
4 a Pump, whereby thefe Creatures might exercife their 
4 Analogous Lungs,and not on|y draw in,but force out the 
4 Air they live by: But thefe were but Coujedhires, and 
4 upon further examination feem'd lefs probable. 
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