780 
ANNUAL REPORT OF NEW YORK 
UIIKHt. PLY. OVIPOSITOR VERY EXTENSILE. 
face. The other or apical joint, b, is long and slender, thickened 
towards its tip, and its whole surface is evenly but thinly bearded 
with fine short erect bristles. The two small finger-like processes 
at its end, a, are cylindrical and four times as long as thick, and 
are also bearded on all sides with erect fine short bristles. 
At the end of the joint, b between the bases of the two pro¬ 
cesses a I have several times observed a short fine hair, which I 
had always supposed to be the protruded end of the sting or long 
bristle mentioned by Kirby and figured l>y Ourtis. I now sought 
to grasp this hair with the point of the forceps, to ascertain if it 
could be drawn out, but I found it and its surroundings so ex¬ 
ceedingly minute that to manipulate it in the proposed manner 
was impossible, or at least required implements more delicate and 
a hand more steady than mine, or than I think Mr. Kirby could 
have possessed when he examined these parts. And I conclude 
the hair I had so particularly noticed was merely one of those 
with which the surface of this joint is everywhere thinty bearded. 
Next, on grasping the finger-like processes with the forceps and 
gently drawing upon them, I found these two telescopic joints of 
the ovipositor to be remarkably extensile, stretching and elonga¬ 
ting as though they were formed of India rubber (caoutchouc). 
In a young and pliant-skinned fly they may thus be drawn out t<3 
thrice or four times the length of the bod)’', and when thus ex¬ 
tended and attenuated, their exposure to the air immediately 
renders them dry and rigid, whereby they remain in this form, 
resembling a slender hair. And thus, should the ovipositor be 
confined in its middle and extension happen to be made only 
on its last joint, this joint would be elongated to resemble a fine 
hair. But I cannot think Mr. Kirby could be thus deceived, sup¬ 
posing he was drawing a fine long hair more and more out of the 
body when he was merely elongating this joint; though from the 
minuteness of these parts there is some liability to such a mistake. 
Again, in an aged fly in which the skin is less supple and ex¬ 
tensile, on grasping the end of the ovipositor and drawing upon 
it, it sometimes tears asunder, whereupon a smooth slender tube 
maybe drawn out from the body to twice or three times its 
length. But this tube is plainly the intestine. Nor do I detect 
any slender hair accompanying it, either externally or internally. 
I am therefore convinced that nothing answering to Mr. Kir¬ 
by’s term and description, “ an aculeus as fine as a hair and very 
