299 
MISCELLANEA. 
Experiments with Prussic Acid. 
This is an amusing trifle by Mr. Scanlan, on the effects of prus- 
sic acid upon the tipula or crane fly (yulgo “ Harry longlegs,”) by 
means of which the curious mechanism of its ovipositor was ob- 
served. Kirby and Spence state that this insect, when suddenly 
caught, shoots out its eggs to a distance of ten inches, but the 
mechanism by which this singular act is accomplished is not de- 
scribed by those able entomologists. Mr. Scanlan thus solves the 
riddle : — 
“ In the month of October, two years ago, when the common 
tipula or crane fly is seen flying about in every direction, I caught 
one of these insects, and held it by the wings over the mouth of a 
large bottle of medicinal prussic acid, which happened to be near 
me at the time. The tipula, which before had struggled hard for 
its liberty, immediately on being presented to the prussic acid 
vapour, became motionless. I now laid it upon a piece of writing- 
paper, in order to examine it with a magnifying glass. After the 
lapse of a few seconds, I observed a convulsive motion, by means 
of which a single ovum was thrown from the abdomen into the 
ovipositor, which is a very curiously constructed apparatus at the 
anal extremity. This convulsion of the abdomen, which somewhat 
resembled the operation of vomiting, appeared incapable of sending 
the ovum any further, leaving its total ejection to the ovipositor, 
which it effected in a most admirable manner. 
“ The ovipositor of the tipula very closely resembles the beak 
of a bird, with both the upper and lower mandible divided longi- 
tudinally, each limb of each mandible being articulated and sus- 
ceptible of motion laterally. The extreme end of the limbs of the 
inferior mandible, when placed together, form a tube. It was at 
the commencement of this tube the ovum was lodged. The limbs 
of the upper mandible now separated themselves, and bent down- 
wards at a right angle with the lower one, which they closely 
embraced, and, with a sudden jerk, shot the ovum through the tube 
formed by the limbs of the lower mandible. About twenty ova 
were ejected in this way, and flung to a distance of about four or 
six inches from the insect. The tipula after some time recovered, 
and flew away. I repeated this experiment upon another female 
tipula with the same result.” 
