VI 
Introduction. 
As far as leisure has allowed, synoptic tables of the genera 
and the species in each genus, the Anofthelinae, Megarhininae, 
Culicinae, Heptaphlebomyinae, and U ranotaeninae have been 
worked out. There has not been sufficient time at my disposal 
to do the same with all the Aedinae, nor with the unbanded- 
legged species of the genus Culex, which form at present an 
unwieldy mass of species. That many errors hav^ crept in there 
can be no possible doubt. 
The system of classification by scale-structure apparently 
works out well from a practical point of view. The object of 
this classification has been to select some method of simple 
grouping by means of which medical men and others working in 
the field can identify these insects. That the characters given 
enable them to do so is proved by the numbers of collections sent 
correctly named, not only by British observers but by the 
French doctors working in harmony with them in Africa. 
Moreover, judging from the little we know of the bionomics of 
the Culicidae of the world, when looked at in a broad view, the 
classification by scale-structure places them in a natural grouping. 
This cannot be said when one considers the larval characters 
that have been given. Two instances may be mentioned:—The 
larvae of Culex scolasticus, Theobald, were said to be those of a 
Janthinosoma ; this species, however, comes very near the type of 
the genus Culex , while Janthinosoma is very distinct in structure. 
The genera Stegomyia, Theobald, and Lejpidoplatys, Coquillett, 
two very distinct and well-marked Culicine genera, were grouped 
under Meigen’s Aedes. 
No one will dispute the importance of knowing the larval 
characters, but in the present state of oqr knowledge the progress 
of economic science will be retarded unless great care is taken in 
founding taxonomic conclusions on the study of the immature 
forms. 
The importance of palpal structure, as pointed out by Neveu- 
Lemaire, is undoubtedly great. It has the disadvantage, how¬ 
ever, that in a type specimen one may be unable to count the 
segments. In consequence confusion may arise, as for instance 
in connection with the genera Toxorhynchites and Worcesteria. 
No one can detect the number of terminal segments in the palps'* 
of these two genera unless microscopic preparations have been 
made. Owing to the dense coating of scales, what look like palpi 
of three segments may really consist of four, five or six. 
I must especially thank Mr. K. F. Carter of the South 
