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Home Nature-Study Course. 



One kind of pockets are round and the other 

 are long; in the round pockets are developed 

 bodies which may be compared to the pollen 

 grains of higher plants, and in the long pockets 

 are developed what may be compared to the 

 ovules of flowering plants. This little, leaf-like 

 structure with its roots and pockets is very small 

 in most species of ferns, often not larger than 

 Fig. 2. P rot hall i u m ^\^q head of a good-sized pin, but in some species 

 greatly enlarged, showing ^^ j^^.^^ -^^ diameter as a Small pea. This leaf- 



the two kinds of pockets ,., ^ , ^ . n , .t ,. .7 n- /i— \ 



, ,, ^, , like first stage is called the prothallium (rig. 2) 



and the rootlets. ° ' v o / 



and it cannot be developed from the spore unless 

 it has plenty of moisture. The prothalliums may be found sometimes 

 in numbers on a mossy log, or on the banks of a stream, but they are 

 so very small that unless the eye is trained to find them they are rarely 

 discovered. Water is needed also for the carrying of the pollen-like 



Photographed by Verne Morton. 



Fig. 3. — An evergreen fern. The common polypody. 



bodies, which grow in the round pockets to the ovule-like bodies, which 

 grow in the long pockets. Among the flowering plants the pollen is car- 



