PLACE-VEGETATION 



229 



386. Plant societies may also be distinguished with refer- 

 ence to latitude and temperature. There are tropical socie- 

 ties, temperate-region societies, boreal or cold-region societies. 

 With reference to altitude, societies might be classified as 



397. A society of sand-dune plants. New Jersey. 



lowland (which are chiefly hydrophytic), intermediate (chiefly 

 mesophytic), subalpine or mid-mountain (which are chiefly 

 boreal), alpine or high-mountain. 



387. The above classifications have reference chiefly to 

 great geographical floras or societies. But there are societies 

 within societies. There are small societies coming within 

 the experience of every person who has ever seen plants 

 growing in natural conditions. There are roadside, fence- 

 row, lawn, thicket, pasture, dune (Fig. 397), woods, cliff, 

 barn-yard, corn-field societies. Every different place has its 

 characteristic vegetation. Note the smaller societies in Figs. 

 395 and 396. In the former is a water-lily society and a 

 cat-tail society. In the latter there are grass and bush and 

 woods societies. 



