296 JOURNAL OF SCIENCE. 
heavier net-wire, to which a pointed net of cheese-cloth is attached. 
On such occasions it is necessary to carry with one a larger bottle 
with a little cotton-wool in the bottom, and a phial of chloroform in 
the pocket. By thrusting the end of the net, with its contents, for 
afew seconds intothe chloroform bottle, one can then remove 
the specimens undisturbed. Very minute flies it is expedient to pre- 
serve alive in small bottles filled with paper clippings and through 
the cork of which a small glass tube is thrust nearly to the bottom. 
For a collecting net, after many experiments and failures, I have 
found most serviceable a simple, rather light, brass wire, soldered 
together to torm a ring about 28cm. in diameter and firmly at- 
tached toa light handle about one metre Jong. The net is made 
ot very coarse bobbinet lace, the most serviceable and, in the end, 
cheapest material. The net should be readily handled with one 
hand. 
For the collection of diptera a few hints here will suffice. The 
best season in New England is June, yet specimens may be collected 
every month in the year. In Mayand the early part of Jure, beat- 
ing will give excellent results. A little later, patches of black- 
berry (Rubus), wild cherry (Prunus), dogwood (Cornus), Canada 
thistle (Civsiwm), or other melliferous blossoms will afford desirable 
specimens. It is bettez to let specimens come to the collector, than 
to go hastily about looking for them. I have spent six hours about 
a patch of Cornus pamculata not ten metres in diameter, and been 
amply repaid. But few specimens are found in shady woods; 
those few are to be sought for there. The favorite place for Taba- 
nid@, as indeed for most flies, is on the border of woods, open 
elades, meadow lands, etc. 
Specimens shouldnot be allowed to remain over night unpinned. 
The large specimens may be pinned through the thorax, preferably 
with japanned iron pins. They should be placed on the pin only 
low enough so that the head may be grasped with the thumb and 
forefinger without danger tothe specimen. The wings should never 
be spread. Spreading not only renders the specimens more difficult 
to study, but it spoils the natural appearance of the insects, and is 
a positive injury to them for the cabinet. All that is necessary is 
to push aside the wings so that they will not conceal the abdomen. 
Minute specimens should be pinned with fine iron wire from the 
underside, and then pinned upon small strips of thin cork, the 
upper surface of which has been covered with white paper, and 
through the other end of which a pin isthrust. Small specimens 
should never be glued to bits of card-board, as is commonly done 
with coleoptera. Only one specimen should be placed on the 
piece of cork. 
The greatest enemy to dipterological collections is dust : insects 
can be guarded against, but it is difficult to exclude dust, unless 
he cases are used. Dampness and mildew do often much mis- 
chief. 
A good dipterological specimen must be unrubbed, unmoistened, 
not dusty nor greasy, and with the wingsunspread. It is quiteas 
easy tocollect good specimens as poor ones, and much more satis- 
factory. 
