RESPIRATORY SYSTEM 



r,o 



crocodiles and chelonia. The occurrence of this state of 

 affairs is not a character of any one group, but it is found 



Tr>. 



FIG. 39. BHKAST REGION OF Manucodia. 

 Tr, trachea ; P.M, pectoral muscle ; Fern, femur. 



sporadically, as it were, in members of quite different groups. 

 The facts have been collected into a general account of the 



