ON THE CLASSIFICATION OF THE FAMILY 259 



the vertex and back of the nape, but alternate with up- 

 right forked scales on the band between. In Anopheles 

 we have again the small lateral patches of imbricated flat 

 scales, but the entire vertex and nape is covered with 

 alternate ranks of narrow, curved, and upright forked scales, 

 such as are found on the limited band across the Ctdex 

 head. In Mdes, the lateral patches of flat scales are so 

 large as to leave only a narrow band between them, which 

 is occupied by a stripe of narrow curved scales, no upright 

 forked scales being present. Lastly, in Sfegomyia, just as in 

 Megarhina, the whole vertex and nape are covered with 

 imbricated flat scales, but instead of forming the entire 

 tomentum, as in the latter genus, the back of the Stegomyia 

 head is additionally provided with a band of scales of the 

 upright forked type. Below the figure of each head will 

 be found one of the corresponding type of scutellum, an 

 examination of which will show that in Giilex and all other 

 Mosquitoes it is covered with long narrow scales, except in 

 the sub-family Megarhinina, and the genus Stegomyia, in 

 both of which this portion of the thorax is wholly covered 

 with flat scales. Below these figures will be found the types 

 of clypei already sufficiently described, and next beneath 

 them three figures illustrating the nude metanotum of 

 Culex, and of all other Mosquitoes, except the two small 

 genera Trichoprosopon and Wyeomyia. In the latter of 

 these, placed to the left, it will be seen that the usually 

 bare surface is armed with a few stout bristles, while in the 

 former, in addition to similar bristles, there are also patches 

 of scales. In searching for the bristles peculiar to these 

 genera, it is well to remember that they are easily knocked 

 off, but that in such case the minute black specks, showing 

 the spot from which they have been detached, can usually 

 be made out. Mucidus has certain peculiar head scales. 



It should be added that in the above remarks, what has 

 been said of Stegomyia applies equally to the closely-allied 

 genus Armigeres, as to the distinctness of which Mr- 

 Theobald himself expresses some doubt. 



At the bottom are given drawings showing the form and 

 arrangement of the scales of the veins of typical Culex, and 



