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Manual of zoology 



The abdomen is devoid in the adult, except at the 

 posterior extremity, of any paired limbs. At the posterior 

 end there are frequently appendages forming the sting, 

 ovipositor and genital processes, which may be of the 

 nature of modified limbs. 



Fig. 145. — Culex, mosquito, and larva. (After Guerin and Percheron.) 



The digestive canal (Fig. 146) consists of a number of 

 parts. It is nearly always considerably longer than the 

 body, and is longer in vegetable-feeding than in carnivorous 

 forms. The mouth leads into a buccal cavity into which 

 the ducts of a pair of large salivary glands open. 



Following upon this is a narrow (esophagus (azs), which 

 dilates behind into a crop (cr) for the storage of food. 

 The place of the crop in sucking insects is taken by a 

 stalked sac, usually termed the sucking stomach, but which 

 is more properly a food reservoir. The essential processes 



