Of the Ox-Fly, or Gad-Bee* 207 
black Speck) being placed in exaffc Order, 
and kept together by a Sort of Jelly or glewy 
Matter, which the minute Maggots, when 
hatched, carry down with them to the Bot¬ 
tom, and thereby cement together the fmall 
Particles of Earth or Sand that form their 
Cells or Cafes. * 
CHAP. XXVII. 
Of the Ox-Fly, or Gad-Bee. 
A NOTHER Creature that undergoes a 
like Change, is the Ox-Fly, Dun-Fly, 
or Gad-Bee, an Infedt very troublefome to 
Cows and Horfes. 
This, like the Gnat, has a long Probofcis, 
with a (harp Dart or Darts fheathed therein. 
The Ufe of thefe Darts is to penetrate the 
Flefh of Animals, and feed on their Blood ; 
whereas the Probofcis can only ferve to fuck 
the Juices, Honies, or Dews, from Fruits, 
Flowers, or the Leaves of Plants : and Pro¬ 
vidence feems to have kindly furnilhed it 
with this two-fold Inftrument, that if one 
Sort of Provifion fails it may be able to fub- 
fifl on the other. It is worth Enquiry, whe¬ 
ther Lice, Fleas, Houfe-Bugs, &c. are not 
alfo provided for the fame Purpofe, 
P 3 Th# 
