. The Journal of hygiene . f insects to a system there is an account of thevarious views held by other entomologists. The accompanying figure (B)shows that the nervures oi Anopheles correspond essentially with thosefigured by Comstock and Needham for Dixa, the chief differences beingthe much greater extension of the subcosta in Anopheles, the failure ofthe second radius and combined fourth and fifth radii to be connectedwith the first, and the presence of the cross-nervure 0. From the diagram it will be seen that each nervure is named afterthe main branch from which it arises, and the differen
. The Journal of hygiene . f insects to a system there is an account of thevarious views held by other entomologists. The accompanying figure (B)shows that the nervures oi Anopheles correspond essentially with thosefigured by Comstock and Needham for Dixa, the chief differences beingthe much greater extension of the subcosta in Anopheles, the failure ofthe second radius and combined fourth and fifth radii to be connectedwith the first, and the presence of the cross-nervure 0. From the diagram it will be seen that each nervure is named afterthe main branch from which it arises, and the different branches aredistinguished by the numerals 1, 2, 3, etc. beginning with that lyingnext to the anterior edge of the wing. When two nervures havecoalesced the resulting nervure is indicated by such a symbol as 7^4+5which indicates that the fourth and fifth radii have fused. The variouscells or areas into which the wing is divided are in this scheme namedafter the chief nervure which takes part in forming its anterior Fig. B. The right wing of a male Anopheles maculipennJs Meigen x about scales have been removed to show the Anal area. 1st A. Anal nervure. C. Costa. Cu. Cubitus. H. Humeral cross-nervure. I. Cross-nervure between R^ and Ri+5. J. Cross-nervure betweenradial and medial systems. K. Cross-nervure between medial and cubital Media. 0. Cross-nervure between R^ and R. Radius. Sc. Subcosta. The cross-nervures connecting the longitudinal ones still remain tobe mentioned. These are the humeral (H, Fig. B) running from thecosta to the subcosta, a very constant cross-nervure ; the radio-medial(J, Fig. B) connecting the system of the radius with that of the medius,and the medio-cubital {K, Fig. B) uniting the medial system with thatof the cubitus. These three are very generally met with, but there is 476 The Structure and Biology of Anojyheles in Anopheles a fourth cross-nervure uniting R^ with R^j^^ {I, Fig. B), thisexists also, but
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