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be found useful, when it is desired to retain temporarily 

 any preparation of particular interest. 



(10) A clean duster, of some soft fabric. 



(11) A few narrow strips of clean blotting paper. 



(b) Preliminary Considerations. 



The following directions are given with the view of 

 providing preparations which will be suitable for 

 furnishing information on the points named, i.e., (a) 

 The presence or absence of mites, both living and 

 dead, and approximately their numerical proportions ; 



(b) the type of infestation, i.e., unilateral or bilateral; 

 the degree, whether initial, actively increasing and 

 showing all development stages, or in final stages; 



(c) the condition of the tracheae, to what extent 

 pathologically affected. 



Conclusions regarding these points can be safely 

 drawn only if the preparation show all parts of the 

 thoracic tracheae liable to be occupied by Tarsonemus. 



For the purpose of differentiating between living and 

 dead mites an anaesthetic cannot be used in killing the 

 bees. This is. best done by firmly compressing the 

 head by means of a stout forceps. A few bees should 

 be treated in this way before commencing operations, 

 and a short interval of time allowed to elapse to permit 

 the reflex movements of the limbs, etc., to cease, 



(c) Dissection Routine. 



After adjusting the microscope for examination with 

 the low power (f-in.), by means of the pipette place 

 a small drop of water in the middle of a clean slide 

 and on this place the bee to be examined, ventral side 

 uppermost. Move the bee to the edge of the drop of 

 water so that the wings adhere to the slide. This helps 

 to steady the bee during dissection. 



Next, with a needle held in the left hand press firmly 

 on the middle line of the thorax somewhere between 

 the second and third pairs of legs. Avoid directing 

 the needle too far forward. This operation should hold 

 the bee steady. 



Holding the scalpel in the right hand, pass its point 

 through the soft chitin behind the first pair of legs, 



