INSTRUCTIONS FOR COLLECTING INSECTS. 167 



have a knob at the end. They must be killed, like the Dragon flies, 

 by applying alcohol with a brush. 



Whife Ants will be found swarming in decayed logs, beneath stones, 

 ■&C. They are very tender, and must be pinned at once. The insects 

 of this order live during the warm weather only, and can be collected 

 in the greatest numbers when the sun shines warmest and the days 

 are fine. Many of them may be obtained by spreading a sheet in the 

 woods or near some stream, among the bushes, during the night, and 

 placing over it a bulls-eye lantern ; the insects will be attracted by 

 the light, and by means of the white sheet they can be more readily 

 seen and taken with the net. This is also a most excellent method of 

 mothhvj during the hot summer evenings. 



INSTEUCTIONS FOR COLLECTING DIPTERA. 



BY H. LOEW, WITH ADDITIONS BY R. OSTENSACKEN. 



The first instrument I use in a locality, the fauna of which I am not 

 well acquainted with, is a linen bag, fourteen inches in diameter and 

 two and a half feet long, a little rounded at the top or apex, and 

 attached to a strong iron ring, with a hollow metallic handle, in which, 

 if necessary, a cane or other piece of wood may be inserted. With 

 this bag I begin to sweep, and in a short time ascertain what insects 

 abound in the grass, on the flowers, or in moist or dry places, &c. 

 After the last sweep, by a dexterous twist of the handle I throw the 

 apex of the sack over the ring, so as to prevent the escape of the 

 insects, and give them time to compose themselves at the bottom. It 

 is then opened, and I insert my head into it to see what I have cap- 

 tured. They immediately begin to move upwards. The common 

 specimens I allow to pass ; but if there is one which I desire to take, 

 I let it advance to the middle of the bag, and then gently grasp it, 

 from the outside of the bag, with the right hand. The other captives 

 I drive down to the bottom by blowing moderately on them, and con- 

 fine them there by letting the ring fall over the right hand, which 

 holds the insect, which is now easily seized with the left hand. This 

 operation is repeated until everything desirable is taken out, when the 

 bag is emptied of its contents by inversion, and the sweeping recom- 

 menced. 



This is the most important of all the implements used by the Dip- 

 terologist. Its employment prevents him from wasting his time iu 

 barren localities, promptly indicates the presence of rare species, and, 

 by furnishing this information, enables him afterwards to have an 

 abundance of specimens. 



When I have, by the use of the bag, discovered the locality of rari- 

 ties, I use another instrument, which is nothing more than an ordi- 

 nary insect- forceps, of the form shown in fig. 1. Here, h is the placo 

 for the thumb, c is the joint placed near the handle in order that the 



