INTEODUCTION 



J 



The present volume deals almost exclusively with new species 

 added since 1903, and at the same time fresh localities and notes 

 are given of previously known mosquitoes. 



Owing to the amount of work done during the past two years 

 it has been found quite impossible to include in this volume a 

 large amount of information gathered together during the last 

 year. This we hope will be dealt with in a future volume. 



The number of specimens received since the appearance of 

 the last volume has been about twelve thousand, and nearly half 

 of these have not as yet been examined. Although a large 

 number are well known species there are apparently many new 

 to science amongst them. 



In this volume one hundred and sixty species are included 

 which have been described since 1903 and seventy-three new 

 species are described here. 



Since this volume went to press a large number of new 

 mosquitoes have been described from America and the West 

 Indies ; many of which seem to be based on insufficient 

 characters. There seems to be a growing tendency to create 

 species upon a few colour variations, especially when they 

 have been found in different localities. It is very doubtful if 

 some of these are more than local varieties of known species. 

 If the frail characters upon which many species are being 

 founded are applied to the large series of Culex fatigans or of 

 Stegomyia fasciata from all parts of the world in the Museum 

 collection, the series would be split up into a very large number 

 of species, and yet every gradation could be found between the 

 two extremes in the series. 



Moreover, in America, Messrs. Dyar and Knab have started 

 " species-making " out of larvae of which the adults are not 

 known. Sooner or later the adults may be described or the 

 named larvae may be fixed to the already described adults, and 



