STORING DIPTERA: THE COLLECTING BOX 415 



To pin a fly proceed as follows : Place the specimen on a piece of 

 cork mat and grasp it gently by the legs between the forefinger and thumb 

 of the left hand. Then insert the pin, either with 

 forceps or the fingers, through the dorsum of the thorax Mounting 

 just behind the suture, and a little to one side of the 

 middle line, pushing it well through and taking particular care that the 

 point does not pass through any of the joints of the legs, or they may 

 come off. The pin should be passed through the fly until it is about 

 the junction of the upper and middle third of the pin. Some specimens 

 should also be pinned on their sides, but in this case the point of the pin 

 should not be pushed right through the thorax, but should stop short at 

 the side wall in order to avoid injuring the bristles in this region ; as has 

 already been noted they are of special importance in connection with 

 the identification in the Muscidae. Cut off the head of the pin with a 

 slanting cut, and pass the cut end into a piece of pith so that the 

 uninjured side is uppermost. The legs and wings are then arranged with 

 a needle, and supported in position with other pins until they are stiff. 



Each specimen should then be mounted on a piece of cork or pith and 

 this in turn mounted on a long firm pin ; a label is attached giving the 

 necessary details of time and place of capture. The labels should be as 

 small as possible and of thin card or stiff paper, the supporting pin being 

 passed through them. The pieces of cork are best prepared by covering 

 a piece of cork mat neatly with paper, and then cutting it into small 

 squares with a sharp knife ; each piece should be a little bigger than the 

 fly. Pith can be bought in sticks which can be shaved off into small 

 strips. 



For the examination of pinned specimens, and for use during the 

 necessary manipulation, a lens magnifying about ten diameters should be 

 used. The best form is one which fits into the eye like a monocle, leaving 

 the hand free, but in the tropics it is essential to have a form which will 

 permit of the free circulation of air between the glass and the skin, other- 

 wise the glass will rapidly become dim owing to the deposition of a film 

 of moisture, which obscures the vision and is most troublesome, neces- 

 sitating constant wiping of the lens. This is best obtained by having 

 a skeleton framework of aluminium to support the eye-piece. 



For storing diptera the method devised by Lefroy and Howlett is 

 strongly recommended. The boxes used by the authors were made at 



a cigar factory, and are of cedar wood, not specially 



,. . f , . , ,,. Collecting Box 



finished so as to be air-tight, but resembling the kind 



made to hold fifty long cigars, only a little longer. It is better to have 



