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joined together near the spiracles by a transverse tube. The 
maggot is thus furnished with a compact hard-tipped apparatus, 
very suitable, with due pressure from behind, to force open 
and gradually enlarge the fine passage leading down, in the 
early stage of attack, from the outside of hide to the embryo 
swelling beneath. The power of pressure, says Miss Ormerod, 
possessed by the maggots at this period of their life is 
enormous, from their power of inflating themselves with fluid 
until they are so hard it is scarcely possible to compress them 
with the fingers, and likewise from their having apparently no 
power of discharging any of their contents. Thus they form 
living and growing plugs, quite capable of pressing back the 
tissues from around them, or from before the small hard tip ; 
but not subject, so long as they continue inflated, to being 
themselves compressed. She had opportunities of watching 
this process of inflation both in worm-shaped maggots and 
when they were slightly more advanced in growth to a club 
or lengthened pear-shape. On placing them in fluid suitable 
for absorption (as in glycerine and water), they became hard 
and shiny, with little trace of the segments which are so 
clearly marked when the maggots are fully developed ; in 
fact, they were almost of a glassy smoothness, save for the 
short bands of minute prickles placed along a portion of the 
back. This hard, almost glassy-smooth outside, with the 
pointed ends at first, and afterwards with the end that needs 
to go foremost being, or nearly so, pointed, makes it peculiarly 
suitable for forcing a passage up the hide. When she put the 
maggots in water, she found the young ones swelled until the 
air-vessels showed beautifully along the side of the smallest. 
They have also the power of exuding quantities of minute 
globules of air on the grey bands of prickly surface. After a 
time they get quite brilliant with the air-globules ; but, except 
at the spiracles, air does not appear elsewhere. On clearing 
the maggots, the air-globules appeared again after a short 
time. 
The size and shape of the perforation through the hide 
altered progressively with the growth of the maggot. At first 
the passage was very little larger at the lower than at the 
upper opening, and though the walls of the perforation had 
now become smooth and shiny, she could not distinguish the 
