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Chapter XV 



, CLASSIFICATION AND IDENTIFICATION 

 OF THE CULICIDAE 



Scales 



Theobald has attached to scale structure the 

 greatest importance from the point of view of 

 generic and specific classification. Hence it is 

 necessary to consider somewhat in detail these 

 structures. Theobald gives the following : — 



Head Scales. — Three forms of scale occur 



(Fig. 47)- 



1. Narrow curved scales. 



2. Upright forked scales. 



.3. Flat scales overlying one another 

 like the tiles of a roof. 

 No. I, 2, and 3 scales found, e.g., Culex. 

 No. 2 and 3 scales only, found, e.g., Stegomyia. 

 No. 3 scales only, found, e.g., Megarhinus. 



Toxorhynchites. 

 Thoracic Scales. — Theobald describes five 

 forms (Fig. 47). 



1. Narrow Hair -like Curved Scales. — They 

 often form a dense feltwork over the mesothorax. 



2. Narrow Curved Scales. — They may occur 

 all over the mesothorax and scutellum, or at the 

 sides of the scutum and in front of the scutellum. 



3. Sptndle-ShapedScales. — These lie scattered 

 about, and never form a complete covering. 



