OR. PLAIN TEACHING. 



217 



parting considerable beauty to 

 landscapes. All the species are 

 deciduous trees, mostly growing 



being produced very early in 

 spring, when the trees are leaf- 

 less, and when flowers are parti- 

 cularly valuable from their rarity. 

 The catkins are also, in most 

 species, so numerous, that the 

 effect of the mass of red, when 

 the tree is seen from a little dis- 

 tance, and in a strong light, is 

 very striking. The females of 

 all the species have their seeds 

 enveloped in abundance of cottony 

 down, 3. Poplars are dioecious, 

 that is, having stamens upon one 

 plant, and pistils on another. 

 The down in which the females 

 of the species have their seeds 

 ! enclosed, flies off when they 

 I are shed, *md adheres to every 

 | object with which it comes in 



to a large size ; natives of Eu- 

 rope, North America, some parts 

 of Asia, and the north of Africa. 

 They belong to the botanical 

 family populus, which is by some 

 supposed to be derived from 

 pallo, to vibrate or shake ; by 

 others, from the use made of the 

 tree in ancient times, to decorate 

 the public places in Rome, where 

 it was called arbor populi, or tree 

 of the people. It has also been 

 conjectured that the derivation 

 from populus was suggested by 

 the tremulous motion of the 

 leaves, when agitated by the 

 least breath of wind, thus being, 

 like the people, easily agitated. 



The catkins of the males, 2, of 

 most of the species are highly 

 ornamental, from the red tinge 

 of their antlers, and from their 

 ,0 



contact. It is like cotton wool in 

 appearance, and has been manu- 

 factured into cloth and paper, but 

 found to be wanting in elasticity.* 

 The black poplar has pointed^ 

 serrated leaves, 4. The tremu- 

 lous motion of the leaves, which 

 ^ is com- 



mon in a 

 greater 

 or less 

 degree 

 to all 

 poplars, 

 proceeds 

 from the 



rives and Slii'ubs. 



