THE COLLECTION AND PRESERVATION OF DIPTERA 55 



THE COLLECTION AND PRESERVATION^^ I B R A . Y ' 



DIPTERA. V'^V -^^-^ 



By Percy H. Grimshaw, F.R.S.E., F.E.S. \C ilT^ vS>7 



The approach of a new collecting season, which promises 

 to the entomologist something like a return to pre-war 

 conditions, has suggested to the writer the desirability of 

 penning a short series of hints on the capture and preservation 

 of Diptera if only to show with what facility a good collec- 

 tion of these interesting insects can be acquired, and how 

 extremely simple are the methods of preparing for the 

 cabinet as compared with those employed for beetles, bugs, 

 or butterflies. Although, of course, a collection of Diptera 

 can never vie with one of Lepidoptera in beauty of general 

 appearance, yet it can fairly be claimed that when the two- 

 winged insects are examined under the lens the more popular 

 group must yield in the matter of interest and variety. 

 The very simplicity, too, of the operations by which flies 

 are rendered available for examination may be used as an 

 argument in favour of their study, for the time occupied 

 in relaxing, setting, carding, and the like, so desirable (if 

 not necessary) in the case of other insects is entirely saved 

 in the case of Diptera, and specimens are ready for examina- 

 tion and identification in the majority of cases after the 

 simple expedient of pinning. Another factor which tells 

 in their favour is that flies of some sort or other may be 

 found anywhere and everywhere, practically all the year 

 round, and at any time of day, while, as a rule, their capture 

 is a comparatively simple process. Moreover, since they 

 are very susceptible ,to the fumes of the cyanide bottle, they 

 die quickly without damaging themselves, and it is not 

 difficult, therefore, to acquire a series of specimens in excellent 

 condition. 



Since flies are ubiquitous it is unlikely that the collector 

 will fail in the acquisition of useful material, provided he 

 choose a suitable day and a good localit}' for work. Consider- 



