methods of killing leps

Kenelm Philip fnkwp at
Sun Sep 20 15:41:33 EDT 1998

	Erik Wahlgren asked about a method of killing butterflies with
one's fingers. 

	There is a standard method of handling collected specimens in the
field called 'pinching'--but it does not kill. You pinch the thorax between
thumb and forefinger while the butterfly is still in the net. This para-
lyzes the flight muscles. If done lightly, the paralysis will soon wear
off. The butterfly can then be placed directly into a glassine envelope,
where it is safe from damage. The pinching is done right through the net

	The technique is described or mentioned in many of the North
American books on butterflies, from Holland through Klots, Ehrlich &
Ehrlich, to Howe and Scott. Holland even provided a drawing of this
technique, although he disapproved of it. Some of these books state
that pinching 'stuns' the butterfly, but Scott refers to killing the
butterfly by pinching. In my experience, pinching neither stuns nor
kills--but merely disables the flight muscles--and sometimes for a
rather short period. I have had pinched specimens recover and take off
just before I got them into the glassine envelope.

	Pinched specimens can live for days in the envelopes. I always
use ethyl acetate to dispatch them later the same day. This can be done
without taking them out of the envelopes.

	Some species are more difficult to pinch than others. I would
not recommend starting on skippers, or on Lycaenids--although the method
can be used on them. Also, some species (as Papilionidae) may require
a surprisingly forceful pinch. In no case do you want to rupture the
wall of the thorax, however--and you must be very sure not to accidentally
include the abdomen in your pinch, or the wings will end up glued to-

	People who believe insects can feel pain may find this procedure
distasteful, to say the least--as Holland did. It does result in better
specimens, and I am unaware that insects have any pain sensors.

							Ken Philip
fnkwp at

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