different (Fig. 60). Here again variations occur in the 

 same species. An accurate description of a wing 

 should comprise all the minute spots on each vein. 



The Wing Fringe. Where each long vein meets 

 the costal vein (which passes right round the wing) 

 there not uncommonly occurs a light area. Note that 

 the fringes of M. rhodesiensis, M. funesta, M. listoni, 

 M. culicifacies differ from one another (Fig. 59). 



The Leg Bands. It must be noted whether the 

 banding, if present, in each segment (tarsus) is apical 

 or basal or both ; whether slight or well marked, etc. 

 Thus N. theobaldi has the last two hind tarsi entirely 

 white, while N. jamesii has the last three hind tarsi 

 entirely white (Fig. 61). 



The Palpal Bands. The palpi consist of four 

 segments. Accumulation of white scales frequently 

 occur at the junction of two adjoining segments 

 forming a band. Here again variation occurs in the 

 same species especially at different seasons of the 

 year (Adie), so that in this and other markings, e.g., 

 leg bands, species must not be founded on too slight 

 differences. 



In M. rhodesiensis the tip of the palpi is black, in 

 M. funesta white, so these two species are easily 

 distinguished. P. marshallii has two broad apical 

 bands and one small basal, while P. costalis (otherwise 

 indistinguishable) has one broad apical and two 

 narrow basal, but as all transitions can be found 

 between these two conditions it is doubtful whether 

 they are distinct species (Figs. 60 and 61). 



The Male Genitalia. It is probable that these 

 will give very important aid in distinguishing species, 

 but very few data on this point exist. It will generally 

 be found necessary to stain and mount the genital 

 segments as directed on p. 144. 



