62 MICROSCOPY FOR BEGINNERS. 



large ones. They are much smaller, narrower, and com- 

 monly contain chlorophyl grains, which, while usually 

 not abundant enough to tint the whole moss a bright 

 green, yet give it that beautiful pale hue almost charac- 

 teristic of it. These cells will probably need to be 

 searched for the first time the beginner studies a sphag- 

 num leaf, as they are not apt to catch the eye. 



The moss seems to have no roots. The lowest parts 

 of the thick mass which it makes are usually dark and 

 partially decayed, and it is there that the Rhizopods are 

 most abundantly found, although many sun-loving forms 

 are equally numerous in the brighter, better lighted up- 

 per parts. On no account should the student pass a 

 sphagnum swamp, nor even a little patch in those places 

 where it grows more rarely, without taking some to be 

 examined at home. Such a gathering will always pay. 



R1CCIA FLUITANS (Fig. 16). 



Near the writer's home this little floating plant (pro- 

 nounced ricksia) is so abundant that it often covers 

 small pools with a layer two inches deep. 

 Elsewhere, on larger ponds, it is not un- 

 common. It often comes to the collect- 

 ing-bottle tangled in the leaves of Utricu- 

 laria, Myriophyllum, or Ceratophyllum, 

 Fig. 16. Kiccia flfi- or it floats on still waters in little patches 



iUms. 



like islands. Its form is seen in Fig. 16. 

 It has no leaves, indeed it is all leaf ; the botanist calls 

 it a radiately expanding frond, with narrow divisions, 



