13 



(1) It may be in the form of a disc and 

 attached by its centre to the centre of the 

 receptacle, the edge being free (peltate}. 



(2) As a rule it is more or less elongated 

 and attached to the side of the receptacle 

 (lateral], (a) either by a point or notch on one 

 side, in this case it is reniform, oval or oblong ; 

 or (b) by the entire length of one side when it 

 is linear. Sometimes the indusium is attached 

 all round the base of the receptacle and 

 it is at first globose and entire enveloping 

 the sorus when young, eventually opening at 

 the summit and then it resembles a cup 

 (call ci for ni). 



3. LIFE HISTORY OF THE FERN 



The spores which are borne inside the 

 sporangium are extremely minute bodies of a 

 dark brown colour resembling the pollen grains 

 of flowering plants in structure, and are like 

 them cells consisting of the living substance, 

 protoplasm, enclosed, as a rule, in a double coat 

 made up of an outer exine and an inner inline. 

 The former is provided with markings and 

 elevations of various patterns. Provided with 

 this double coat spores are capable of resisting 



