204 



AQUATIC PLANTS 



appearance when in flower, readily obtained from dealers, there is no 

 reason why it should not be better known. As will be noted in illus- 

 tration, it propagates from runners, but the seeds also germinate under 

 favorable conditions. The plant is of European introduction. 



WATER LETTUCE 



Pistia stratiotes is a floating plant with fluted, light-green, velvety 

 leaves, forming a rosette. It likes plenty of heat, a moist atmosphere 

 and protection from the sun. Under favorable conditions it grows to 

 a diameter of about four inches or more and is very attractive indeed. 

 The roots sometimes attain a length of eighteen inches, but they are 

 not sufficiently dense to use for spawning purposes. Multiplies rap- 

 idly in a congenial environment, but degenerates and dies out in a dry 

 atmosphere. 



Fig. 193. Water Lettuce (Tzvo-thirds sice) 



WATER FERN 



Not looking particularly fern-like, the \\'ater Fern, Ccratopteris 

 thalictroides, is the only truly aquatic species of the fern family. It is 

 of comparatively recent introduction into the aquarium and indoor 

 pool, it being more suited to the latter. In a partially shaded posi- 

 tion in the greenhouse it grows into floating masses a foot or more in 



