BY W. R. COLLEDGE. 51 



alive, so it is in a perfectly natural position. Its body hangs 

 nearly parallel to the surface upon which it rests. It is supported 

 by the fore and middle pair of legs. The hind pair curl back- 

 wards and project into the air. If ever you see a mosquito with 

 its hind legs in that position, you may be sure it does not belong 

 to the Anopheles variety. The latter uses the whole of his six 

 legs to support itself. They are very long, the hinder ones much 

 more so than the front. When they are planted firmly down 

 the body projects at an angle varying from 80 to 45 degrees. 

 The next slide (Fig. 9) is a natural photo, of one of these gentle- 

 men. He was good enough to allow me to operate upon him, 

 and the position shows very distinctly the difference between 

 them and the ordinary mosquito when at rest. They can be 

 picked out by any ordinary observer. 



Another distinguishing feature is their spotted wings. One 

 variety of the ordinary kind, usually called the Scots grey, have 

 faintly spotted wings, but the marks are not nearly so distinct 

 as in the Anopheles. In the figure (No. 3 2) the dark spots and 

 light spaces are clearly manifest. In the light portions the 

 scales appear to be absent, but a careful search shows them to be 

 still there, but almost devoid of colour. This peculiarity of the 

 wings is most beautifully seen when the microf:Cope is arranged 

 for dark ground illumination. The nervures of the wings are 

 traversed by a double row of scales, set at an angle to each other, 

 and a deep fringe of long sword-shapen ones hang from the 

 lower border of the wing. The next slide (Fig. 11) shows this 

 beautiful fringe. Here is one with scales taken from various 

 parts of the body. They differ a good deal in shape, and are 

 inserted like shingles on the roof of a house, the tip of one being 

 overlapped by the base of the next. An exception to this is 

 found on the back of the head ; here the scales are wedge-shaped 

 and set upright like plumes. 



Certain appendages of the head differ from the ordinary 

 mosquito. One of these is the length of the palpi in the female. 

 On the screen is the head of a female of the common kind. The 

 palpi are short, not more than one-fifth of the length of the 

 proboscis. In the next view (Fig. 13) is seen the head of the 

 female Anopheles. The antennae stretch out on each side, but 

 the palpi are prolonged until they nearly equal the proboscis in 

 length. That is a characteristic feature of this family. 



The male organs of the head also have their peculiarities. 

 The succeeding slide (Fig. 14) shows the proboscis in the centre. 

 The palpi are longer, and near their tips expand into a club-like 



