20 DIPTERA OF AUSTRALIA, 



sufficient for the collection and preservation of Diptera. The 

 larger species I generally capture with a small bag-net made of 

 very fine silk gauze, and the smaller ones by means of a glass tube 

 charged with chloroform or benzole. The tube is prepared in the 

 following way : — a piece of cotton-wool moistened with one of the 

 above is inserted into the end of the tube, pressed tightly down, 

 and covered by a circular piece of blotting-paper. Of course 

 when not in use the tube is kept corked. "When a large insect 

 has been captured in the net, take one of the chloroform tubes 

 and secure the insect in it against the side of the net; then, 

 with a little manipulation it is easy to put in the cork, and the 

 insect dies almost instantly. Having left it there for a short 

 time it is taken out and pinned in a cork-bottom collecting box, 

 and there is no further trouble with it ; but ixnless specimens 

 are afterwards carefully kept in a tight box provided with a lump 

 of camphor they will speedily be destroyed by mites or some of 

 the small beetles prejudicial to natural history collections. In 

 using the glass-tul^e for capturing, the insects must always be at 

 rest, and as they may be commonly thus found under the ledges 

 of overhanging rocks, on logs, and in similar situations, it is 

 generally an easy matter to place the mouth of the tube gently 

 over them ; they will immediately fly up the tube which must 

 then be quickly corked. When resting on a flower or a leaf 

 the palm of the hand may be employed to inclose the insect 

 within the tube. Should the inside surface of the tube be 

 at all damp it is necessary to uncork and expose it for a few 

 seconds to the drying influence of the atmosphere, othenvise, 

 enclosed insects, especially if they be very minute, are liable to 

 adhere to the glass, and their wings and antennai to be spoiled. 

 As soon as the insects are dead they must be transferred to a pill- 

 box, and carefully placed between layers of soft fresh leaves or 

 petals of flowers, so as to prevent shaking, while the moisture from 

 the leaves will prevent them from becoming brittle, and thus liable 

 to get broken. On reaching home they should be at once unpacked 

 and neatly gummed on small pieces of card, and pinned through 

 the latter. A slight dot of gum will suffice. The insects should 



