740 CHARLES PAUL ALEXANDER 



Ctenophora angustipennis is recorded as doing secondary damage to prune 

 trees in Oregon (Lovett, 1915). Fuchs (1900) records four species 

 Tipula scripta, T. marginata, Nephrotoma cornicina [as iridicolor], and 

 N. quadrifaria as injuring young plants of both deciduous and conif- 

 erous species. Taschenberg (1880:54) describes Tipula flavolineata and 

 Nephrotoma crocata as destroying year-old seedlings of fir and larch. 

 Matsumura (1916:466) records the larva of Nephrotoma makiella as 

 injurious to the mulberry (Morus) in Formosa. 



METHODS OF EXPERIMENTAL PROCEDURE 



Collecting 



The larvae of the larger species of crane-flies, such as those of the genera 

 Tipula, Pedicia, and Eriocera, may be readily discovered in the field, 

 but the immature stages of the smaller Tipulidae are not so easily found. 

 It is necessary to bring into the laboratory large quantities of the material 

 in which the immature stages are supposed to be living, and there to 

 examine it with considerable care. In the case of mud or earth, it is 

 better to wash away the finer silt particles and examine the residue. 

 The writer has found it most convenient to use a Simplex water-net, 

 placing in it a handful of earth and holding it underneath a running faucet . 

 The mesh of this net is of sufficient diameter to retain any crane-fly larvae 

 except the very young stages. When the fine particles have been removed 

 the residue can be examined in water in white enameled or porcelain 

 dishes, and the larvae and pupae may be easily detected in the water. 

 Numerous associated forms of life will be found, and these should be pre- 

 served or recorded. 



The immature stages of wood-inhabiting species are most easily found 

 in the field by a patient and painstaking examination of the removed 

 bark and the exposed parts of the tree stump or trunk. Moss-inhabit- 

 ing species, such as those of Liogma and many tipuline forms, may be 

 shaken from their haunts onto a piece of white oilcloth, where they are 

 easily observed. 



Killing and preserving 



The larvae and pupae to be studied should be dropped into boiling water 

 for a brief instant. The larva, on contact with the water, at once expands 

 to its maximum size, the spiracular disk is spread wide open, and the anal 



