FERNS AND THEIR RELATIVES of 
Our last two plants are very inconspicuous connections 
of the fern family. They are not only retiring in appear- 
ance, but also in their residence, for the one lives wholly 
under water, and the second grows just on the edge of 
lakes, and is generally submerged the whole winter. 
The first is called the Quillwort, and the second the 
Pepperwort. Both have grass-like leaves, but those of 
the Quillwort are stouter, sharply-pointed, and consider- 
ably swollen at the base. 
Their interest for us lies wholly in their method of 
reproduction. In all the other plants mentioned in this 
chapter the spores are, so far as we can tell, all alike. They 
give rise to similar prothallia, which may bear both kinds 
of cells necessary for reproduction, or only one kind, but 
in either case the prothallium and spore appear the same. 
Now, in these two cases, the Quillwort and the Pepper- 
wort, the difference we shall find in the flowering plants 
between stamen and pistil is anticipated, and they form 
two kinds of spores. There is a large spore, which 
forms a prothallium, on which archegonia (the long- 
necked, flask-shaped bodies pictured on page 74) are 
present, and there are small spores, very like pollen- 
grains in appearance, which can hardly be said to form 
prothallia at all. They split up almost at once into the 
moving pieces of protoplasm (antherozoids), which swim 
off to find an archegonium in which the canal-cells have 
turned to mucilage. 
So we leave the ferns and their company. They have 
the double set of cells for reproduction which we noticed 
as a mark of progress, but they have not learned to . 
combine that machinery with the full vegetative life. 
How that problem has been solved in the flowering plants 
we shall see in the next chapter. 
