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CORVIDjR. 



end of the first bone of the bronchia, and is marked /. Its 

 counterpart passes from the place of separation downwards 

 and forwards to be inserted belowthe extreme point of the last 

 bone of the tube, and is marked e. Within the angle formed 

 by the separation of these two muscles, a third slender and 

 cord-like muscle arises, which goes off to be inserted upon 

 the sternum, as in those birds having one pair ; these are 

 marked d. The fourth muscle, marked A, is the shortest of 

 the five. It arises near the centre of the bottom of the tube, 

 and its fibres, directed obliquely backwards and downwards, 



