How to examine and describe an Anopheles 



parts are the wings, the male genitalia, and the male and female 

 ungues (especially the ungues of the fore leg in the male). 



The wings are best mounted dry beneath a thin coverslip, which 

 may be kept in place by strips of gummed paper or by ringing it 

 with thick Canada balsam. The wings should, of course, be mounted 

 perfectly flat. 



The male genital ia and the ungues should be mounted beneath 

 thin coverslips in xylol balsam. 



The examination of adult Anopheles. For the examination of 

 adult mosquitoes a low power microscope (half or two-thirds inch 

 objective) is necessary. The mosquito 

 to be examined (which has already 

 been mounted on a card-disc in the 

 usual manner) is fixed by a pin thrust 

 through the edge of the card-disc to a 

 flat cork about an inch square. This 

 piece of cork carrying the mosquito 

 is placed on the microscope stage, and 

 can be moved about at will (fig. 6). 

 The angle at which the pin is fixed in 

 the cork should be such that the part 

 of the mosquito which is being exa- 

 mined is always as nearly as possible 

 parallel to the microscope stage. 



In order to be in a position to give a 

 complete description of a mosquito, it 

 is best to begin with an examination 

 of the palpi, proboscis, arid antennas, and to work backwards, noting 

 every marking and character that presents itself. The position of 

 the disc carrying the mosquito will of course have to be frequently 

 altered by removing the pin from the cork and readjusting it at a 

 different angle. The character of the antennaa will at once show 

 whether the mosquito is a male or female, and the length and 

 characters of the palpi whether it is a "culex" or an "anopheles." 

 (See PI. Ill, figs. 1 to 4.) In the examination of the palpi it will also 

 be noted whether they are uniformly coloured or whether they are 

 encircled with white bands, and the number, relative size, and posi- 

 tion of any such bands will be described. (See coloured plates.) In 



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6. 



