102 MORPHOLOGICAL TYPES 



Joining of cortical and medullary tissue to form the 



adrenal bodies ; 

 Parathyroid glands ; 

 Salivary glands. 



Characters of Triton which are specialised when compared 

 with higher forms : 



Reduction of bone in the skull and girdles ; 

 Absence of membrane-bones in the pectoral girdle ; 

 Incompleteness of the interauricular septum ; 

 Degenerate condition of the ear. 



Characters of Triton which are typical of Amphibia : 



Heart with two auricles and single undivided ventricle ; 

 Skin naked, i.e. without horny scales ; 

 Aquatic larval stage. 



