ADI ANT UM PEDATUM. 12 1 



g. Draw a sporangium. 



//. The place of attachment. Scrape away most of 

 the sporangia from an indusium, mount it, and 

 notice the place of attachment of the remaining 

 sporangia and of the bases of the stalks of the 

 others. Observe its relation to the vein. 



/. The mode of dehiscence. Tear off a bit of indu- 

 sium bearing a few sporangia, from a dried speci- 

 men previously soaked in water, place on a slip 

 without a cover glass and allow it to dry while 

 examining it with a low power, illuminating it 

 from above. Watch the process of bursting care- 

 fully. 



j. The spores. In unbursted sporangia from alco- 

 holic specimens notice how closely they are 

 packed. Examine some which have escaped, 

 and note 



Their shape and contents. 

 Their double walls. Burst some spores by 

 pressing on the cover. In favorable speci- 

 mens the outer layer of the wall, exospore, 

 will be ruptured and the delicate inner layer, 

 endospore, with its inclosed protoplasm will 

 be seen protruding. 



D. THE PROTHALLIUM. Carefully brush away all the 

 dirt from the under side of a prothallium of medium size 

 and mount it with the under side uppermost. Examine 

 with a low power, and notice 



1. The shape and the character of the margin. 



2. The shapes of the cells. Draw a few cells of the 

 prothallium showing the various shapes. 



3. The abundant chlorophyll bodies. 



