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T A B. IX. 
D I P T E R A: Muscæ, Ordeu I. 
A wing of the frf Order, with its 'Tendons, carefully delineated. 
Generical Characters. 
The abdoir.en is divided mto four eLvmuh, exclufive of the anus. The inferior edge of the wing 
is not marginated. The tongue is fleflrj, having two lips at its extremity formed for fucking liq^uids. 
It hath the ftemata or three little eyes on the top part of the heed, which are the only organs of 
vifion this infedi hath. 
It has been an opinion generally received and enforced by authors of good credit, that the two 
hernifpherical parts placed one on each fide the head, were the eyes of the rnufea : whatever may be 
their office in any other genus it is not fo in this. I had formerly many doubts of this circum- 
ftance, both from the magnitude of the parts and their dull and languid appearance, with many 
other cbjedlions needlefs to 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 cem- 
pofed of white lead and gum water, carefully covered thofe hernifpherical parts all over. Then 
taking the infedl to the fartheft part of the room from the windows, let it loofe. It was no fooner 
di [engaged, but Jleiv dire Illy to the windows, forceably beating againft the glafs, as endeavouring for 
its enlargement . I then began to fear that I had not effedtually covered the parts, and therefore 
caught it again, and examinin’^ the head clofely with a good magnifier, found that I had covered 
the parts fufficiently, at the fame time carefully viewing the ftemata (the parts which I had be- 
fore fufpeàed for eyes ) confdered their fituation, their brilliancy, and how carefully nature had 
guarded them from harm, it was natural for me to conclude thefe were indeed the eyes. I then 
caught another fly of the fame kind and covered the ftemata carefully, then retreating from the 
windows, let it loofe, when inftead cf flying to the windows as the other had done, it hopped from 
my hand to the ground, inhere it lay ftruggling on its back for fome time, but recovering its fleet 
made fever al attempts to fly, going about a foot at a time, but always fell on its’back -, neither did it 
in miy of its efforts make toward the light, taking no more notice of the windows than any other 
part of the room : and to be flsort, ailed in every refpell as totally void of fight. I tried the ex- 
periment on fever al more cf them, but their allions were fimilar to the firft : by which I was con- 
vinced that the ftanata were organs of viflion, and that the mufea particularly hath no parts by 
which they can difeover an objeA but by them. I cannot call them therefore by any other term than 
eyes-, and they are not only fo in this genus, but I will venture to affirm them to be fiich in whatever 
tnfeA they may be found, for reafons I fkall give in another place. The aforementioned parts 
which appear like cheeks, I have in the coiirfe of this work termed the larger eyes, becaufe in fome 
infelts which have not the ftemata, providence may have adapted them for fuch purpofes, and as 
there is no other term hitherto given, I hope the impropriety will be excufed. In mofl fpecies of the 
Mufea the male is diftiuguifloed by the larger eyes meeting together on the top of the head, but in 
K others 
