{ 33 ) 
TAB. IX. 
D I P T E R A: Müscæ, Order I. 
A wing of the firfi Order, with its deadens, carefully delineated. 
Generical Characters. 
I^he abdomen is divided into four annuli, exdujive of the anus. ‘The inferior edge of the wing 
■is not marginated. ■ The tongue is flefty, having two lips at its extremity formed for fucking liquids. 
It hath the ftemmata or three little eyes on the top part of the head, which are the only organs of vifion 
this infeil hath. 
It has been an opinion generally received and enforced hy authors of good credit, that the two 
hemifpherical parts placed one on each fide the head, were the eyes of the mufea : whatever may be their 
office in any other genus it is not fo in this. I had formerly many doubts of this circumjlance, both from 
the magnitude of the parts and their dull and languid appearance, with many other objections needle fs 
io mention. Determined to fatisfy myfelf of the truth, I caught one of the large blowing flies, or blue 
bottles, as they are vulgarly called, and with an opake fubflance compofed of white lead and gum water, 
■carefully covered thofe hemifpherical parts all over. Then taking the infeCt to the farlhefl part of the 
room from the windows, let it kofe. It was no fooner difengaged, but flew dire Illy to the windows, 
forceahly beating againfl the glafs, as endeavouring for its enlargement, I then began to fear that I had 
not effectually covered the parts, and therefore caught it again, and examining the head clofely zvith a good 
magnifier, found that I had covered the parts fluff ciently -, at the fame time carefully viewing the flemmata 
f the parts which I had before fufpeCiedfor eyes) confidered their ftuat ion, their brilliancy, and hozv care-, 
fully nature had guarded them from harm, it was natural for me to conclude the fe were indeed the eyes. 
I then caught another fly of the fame kind, and covered the flemmata carefully, then retreating from the 
windows, let it loofe, when inflead of flying to the windows as the other had done, it hopped from my 
hand to the ground, where it lay ftruggling on its back for fame time, but recovering its feet made fever al 
■attempts to fly, going about a foot at a time, but always fell on its back -, neither did it in any of its efforts 
make toward the light, taking no more notice of the windows than any other part of the room : and to 
be floor t, aCled in every refpeCt as totally void of fight. I tried the experiment on fever al more of them, 
hut their actions were fimilar to the firft : by which I was convinced that the flemmata were organs of 
vifion, and that the mufea particularly hath no parts by which they can difeover an objeCt but by them. 
1 cannot call them therefore by any other term than eyes and they are not only fo in this, but 1 zvill venture 
to afldrm them to be fluch in whatever infeCt they may be found, for reafons I floall give in another place. 
The aforementioned parts which appear like cheeks, I have in the courfe of this work termed the larger 
eyes, becauje in fame infeCts which have not the ftemmata, providence may have adapted them for fuch pur- 
pofes, and as there is no other term hitherto given, I hope the impropriety will be excufed, Inmoft fpecies 
of the Mufea the male is diflinguifhed by the larger eyes meeting together on the top of the head, but in 
K others 
