70 THE MICROSCOPE. May 
Preparation of Insects and their Parts. 
By J. TEMPERE, 
PARIS, FRANCE. 
[Translated from Le Micrographe Preparateur. ] 
Whole Insects.—The preparation of a whole insect is 
not very difficult, but it requires knowledge, patience and 
care. The time of immersion in potash varies, not only 
in the different genera, but also in the species; in certain 
of the spiders, for example, the immersion ought to be 
prolonged not more than five or six hours. It is the 
same in some of the smalJl orthoptera, while for other 
species in both of these genera twenty-four to thirty-six 
hours are necessary. If we take insects from the class 
Coleoptera, the time and the difficulties increase with the 
thickness of the chitine, and the time will then vary 
from eight to forty days, and it is even more for the 
larger species. It thus becomes necessary for the opera- 
tor to follow daily and attentively the action of the 
potash, and it is only when the insect has become clear, 
and when certain parts, as the head for example, c¢om- 
mence to allow the light to be seen through them that it 
is time to take them out of the alvoline bath and to pre- 
pare them without delay before they separate. 
In general, when taken from the bath, the imsects are 
sufficiently soft and their parts more readily broken so 
that it is necessary to move them with great care in a 
saucer or a little curved plate half filled with distilled 
water. Place the insect upon its back and arrange 
the legs in as naturala position as possible on either side 
of the body, using fine pincers and a mounting needle. 
Then arrange the antenne, the palpi and the principal 
pieces of the cheeks in their places. That done, place 
the end of the middle finger of the right hand upon the 
thorax, that is to say, between the pairs of legs, and press 
lightly towards the abdomen. | 
