vi PREFACE 



become mildewed, which would probabl)' ruin the specimens ; a 

 circular piece of white blotting paper should be placed over the 

 leaves, and frequently renewed. Flies should remain in the bottle 

 till they are thoroughly relaxed, which will require a day or two; if 

 left too long they become rotten and easily break whilst setting. 

 Narrow boards, such as are used for the smallest lepidoptera, will be 

 suitable for large and medium sized flies ; small ones m?iy be set on 

 strips of flat cork, covered with thin white paper. Entomological 

 forceps will be needed to insert the pin in the thorax of the fly ; I 

 prefer these curved, as they are also useful for moving pinned specimens. 

 If the flies are to be photographed the pin must be cut off as short 

 as possible above the thorax, and the cut end blackened with a touch 

 of " matt black." No. 20 pins will be useful for most flies, though 

 the large species require something stronger, whilst the very small 

 ones, if pinned at all, require the finest silver pins obtainable. Taylor, 

 New Hall Works, Birmingham, will supply a sample card of pins. 

 For setting, strips and triangles of stiff writing paper, to hold legs 

 and wings in place, and a stiff sable paint-brush, a few handled bristles 

 and a fine needle or two, also handled, will do all that is required : a 

 lens is indispensable in setting small flies, and may with advantage 

 be mounted on a simple stand to leave both hands free. Some flies, 

 especially the Tachinidae, are very brittle : care must be taken in 

 manipulating" them. Culicidae should be set and photographed as 

 quickly as possible, they very soon shrivel. Other flies may remain 

 about ten days on the setting boards. As to numbers, half a dozen 

 specimens should be ample, both sexes being represented, where 

 possible. Fewer will often have to suffice with rare species, and for 

 purposes of photography one well set specimen would be sufficient, 

 were it not for the ever present risk of damage in moving from the 

 store box : the slightest touch or jar will often cause the loss of a leg 

 or antenna, and the attempt to replace these is seldom successful. 



Store bo.xes may be had in man)- sizes (10x8 inches is as good 

 as any) ; whatever size is used should be adhered to, as far as possible, 

 for the sake of uniformity. They should be carefully examined for 

 mites, a great enemy to the collector ; even new bo.xes are sometimes 

 contaminated. In sending flies by post it is well to use two boxes, 

 pinning them well into the inner, and supporting them by extra pins 

 if possible ; then packing the box with shavings inside a larger one. 

 The label will of course be tied on. When finally pinning flies into 

 the store box it is essential to use a small label giving date and 



