Some more objections. 



6. Species of which the eggs and larvae the characters of 



which are at least as important as the shape of the wing 

 scales in the adult insect are essentially different (e. g., 

 culicifacies and turkhudi) are placed in the same genus, 

 while those with eggs and larvae of the same type are 

 placed in different genera. 



7. The distinctions between the different genera are not of 



equal value, for whereas gigas and rossi, for example, 

 are placed in different genera because in the one case 

 the wing scales are " lanceolate," while in the other they 

 are " mostly long and narrow," the fact that the abdomen 

 of stephensi is densely covered with scales, while that of 

 maculatus is, practically speaking, entirely free from them, 

 is not considered sufficient to warrant these two species 

 being placed in different genera. The same argument 

 may be used with reference to willmori and some of the 

 other species in the genus Nyssorhynchus. 



It appears to us, therefore, that while differences in scale struc- 

 ture are undoubtedly of great value in the distinction of species, 

 such differences as are present at any rate among "anopheles" 

 are not sufficiently important to be considered of generic value, 

 and it is for this reason that we have retained the generic term 

 anopheles for all the species described in this book. In a later 

 chapter we shall refer to this subject in more detail, and give our 

 own method of classifying these insects, but before doing so we 

 must describe the methods by which they may be caught, examined, 

 and identified. 



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