14 MOSQUITOES OF NORTH AMERICA 



Early in 1906 Coquillett published a paper in which the genus Culex, as gener- 

 ally understood, was divided on a scheme based on characters of scales, of 

 coloration and of the female claws. Two new genera are proposed. Later in the 

 same year Coquillett published a classification of the American Culicidee which 

 attempted to harmonize the generally accepted ideas of the classification of the 

 imagos with the new facts brought out by others in the study of the larvae. The 

 palpi as a primary basis of division are definitely abandoned, the presence or 

 absence of lobes on the scutellum forming the first division, and the subfamily 

 Aedinae is discarded. Coquillett recognized seven subfamilies, Anophelinse, 

 Megarhininae, Psorophorinte, Culicinae, Deinoceritinse, Uranotaeniinge, and Tri- 

 choprosponinae. He also added several new genera. 



In 1907 Theobald's fourth volume appeared. He excludes the corethrine 

 forms but otherwise adopts Lutz's modification of his classification. Ten sub- 

 families are recognized with 104 genera. The characters of the subfamilies are 

 essentially those given to genera in the first volume; the characters of the 

 genera are now based almost wholly upon modifications of the vestiture, in some 

 cases on peculiarities present only in one sex. The palpi are utilized as a 

 primary character and in consequence, where only one sex was known, the posi- 

 tion of the insect was assumed. An attempt is made to restrict the genus Culex 

 on genitalic characters, but it is not carried out consistently and the genus is left 

 as a recipient for miscellaneous residue. Other inconsistencies appear, which 

 add to the inherent diflBculties of Theobald's classification. 



Dyar and Knab published in this year a classification based on adult char- 

 acters, excluding all secondary sexual characters and all founded upon the 

 vestiture, recognizing the Corethrinae and Culicinae as subfamilies and dividing 

 the latter into two tribes, Culicini and Sabethini. In 1908, Williston, in the 

 third edition of his " Manual of North American Diptera," adopts this classi- 

 fication. A modification of this classification is employed in the present work. 



In 1908 a work by Peryassu, on the mosquitoes of Brazil, appeared. It fol- 

 lowed closely the classification of Lutz as elaborated by Theobald- Two new 

 genera and a number of new species appear. The systematic part is followed by 

 chapters on the larvae, biology, and kindred subjects. Here the subfamily 

 Stegomyinae is created on larval characters and the following genera included in 

 it: Stegomyia, CarroUia, Stegoconops, Gualteria, Hcemagogus, and Bancroftia. 



In addition to the Avorks discussed many genera have been founded by different 

 workers who have very generally accepted the Theobaldian classification, often 

 even exceeding him in the differentiation of scale characters. It is not necessary 

 to enumerate these here. It should, however, be pointed out that the differences 

 in the interpretation of the terminology of scale characters has caused great 

 confusion and much burdensome synonymy. 



Mention should be made of some works which, while they have not contributed 

 new ideas on classification, are nevertheless important. In 1900 appeared Giles's 

 " Handbook of the Gnats or Mosquitoes." It marks an epoch in that it was the 

 first attempt to bring together the knowledge of the mosquitoes of the world. 

 Of necessity it was largely a compilation, but it contains identification tables 



