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Chapter XII 

 INTERNAL ANATOMY OF MOSQUITOES 



The Alimentary Canal 



The alimentary canal is specialized on account 

 of the blood-sucking habits of the mosquito. It 

 differs from many insects in not possessing any 

 caecal diverticula of the mid-gut. It also differs 

 in the possession of five malpighian tubules, these 

 being in insects usually even in number (Fig. 30). 



The parts of the alimentary canals are as 

 follows : — 



The mouth ) 



The pharynx with pumping organ f The fore- 

 The oesophagus ( gut. 



The oesophageal diverticula ) 



The homologue of the proventriculus"| ry-, ■■. 

 The stomach (so-called) f ^ 



The pylorus ) ° 



The pyloric dilatation ) 



The small intestine fThe hind- 



The colon (" gut. 



The rectum with rectal papillae ) 



The mouth, pharynx, and oesophagus are 

 ectodermal in origin, and both the mouth and 

 pharynx are lined with chitin. The hind- gut is 

 also ectodermal in origin ; it does not possess, 

 however, any portion lined with chitin. The 

 . K 



