METHODS OF COLLECTING AND PRESERVING DROSOPHILINE. 47 
on which the specimen was found, etc.) should be placed on a separate 
label. 
It is often not convenient to mount specimens as they are collected. 
I have found the following method very satisfactory for keeping 
material until it is mounted: A paper tube is made, by wrapping a 
small piece of paper around a pencil and bending in one end so it 
will stay closed. This is then filled with specimens, which are shaken 
down (before they become thoroughly dry and brittle), until they do 
not rattle around. Such a tube, with the upper end folded in so as 
to stay shut, and properly labeled, may be kept indefinitely so long 
as it is kept free from mold, dermestids, and ants. Ht will also stand a 
surprising amount of rough treatment, provided the specimens are not 
too loosely packed. When one is ready to mount the specimens he 
has only to place the tube in a moist chamber for a day or two. Then 
when it is unrolled the specimens will be relaxed and ready for mounting. 
A collection of small Diptera is not as difficult to keep up as is a 
collection of larger insects, for the reason that dermestids do not 
very often attack such small forms. One must, however, keep such 
specimens in tight wooden boxes, and moth-balls should be kept in 
the boxes. If ordinary pins be heated red hot and their heads stuck 
into moth-balls, the latter may then be readily stuck in the insect 
boxes. If a collection does become infested, a liberal dose of carbon- 
bisulphide fumes will remove the difficulty. 
A microscope is necessary for the study and identification of most 
Drosophiline. <A binocular will be found most convenient. When 
examining pinned specimens two flat pieces of cork fastened together 
at a right angle will be found very useful, as they will enable one to 
examine the specimen from any angle, and yet have it held steady. 
Reflected light should ordinarily be used; but for the details of wing- 
venation transmitted light is sometimes necessary. 
