45 WAYSIDE AND WOODLAND BLOSSOMS. 



The Duckweeds (Lemnd). 



The Duckweeds Shakespeare's " Green mantle of the 

 standing pool " are plants that are well-known to everybody, 

 and consequently very few persons know anything of them. 

 This is a paradox ; but they are so common and so small that 

 the average man or woman is content to know them in the 

 aggregate, and cannot condescend to a more intimate acquaint- 

 ance with individuals, or with the different species, yet like 

 many other small things " unconsidered trifles" they are 

 very interesting to the botanist ; for these are among the 

 smallest and simplest of the flowering plants. Taking up two 

 or three plants from one pond and comparing them with some 

 from another piece of water, we shall probably find a difference 

 in them ; but they are all possessed of a more or less flattened 

 green body that floats on the water, and which we shall be 

 inclined to call a leaf. It is not a leaf, however, but a plant 

 that produces no leaves, though it has roots and flowers. To 

 be more accurate we will call it a frond, from whose under- 

 surface there goes down one or more simple unbranched 

 roots, and in clefts of whose margin are simple flowers. The 

 flower consists of an envelope or spathe (see page 15), within 

 which is a bottle-shaped pistil, with one or two stamens beside 

 it. Some authorities conte'nd that the pistil and each of the 

 stamens is really a distinct flower similar to those in Arum. 

 These flowers are so minute that they are rarely seen, and so 

 are thought to flower only occasionally. The plant is chiefly 

 multiplied by the production of new fronds from its edges. 

 The four species figured give the whole of the genus, so far 

 as Britain is concerned ; but three others are known in foreign 

 waters. The differences in the natives may be thus briefly 

 enumerated : 



I. Least Duckweed (Lemna minor). The most frequent species. Frond not 

 more than a quarter of an inch long, egg-shaped, the top flat and bright green, 



