94 



ten or tweh-e feet high. Two broad-leaved grasses, curiously 

 enough, representing the two extremes of the grass gamut, were 

 still more conspicuous — the one, Indian corn {Zea Mays) which 

 occupied much cleared land, standing at the lower end of the 

 scale, and wild-cane {Arimdinaria tecta) which occupied much 

 untamed land, standing at the high end of the scale. 



The remains of a snow and ice storm were evident in South 

 Carolina. Snow and ice were plentiful in North Carolina, where 

 the pine trees of the South were laden to the extent of a decided 

 drooping of the branches which added considerably to the 

 desolate outlook not at all typical of the South, but quite typical 

 of the winter state of the continent thence northward. 



John K. Small. 



RUBBER PLANTS' 



Rubber is one of the most important and the most widely used 

 of plant products. First of all, it is material for water-proofing 

 garments and foot wear, a matter of much comfort to the human 

 race. The consumption of rubber in making automobile tires 

 is enormous. It serves many other uses in the arts and in- 

 dustries. 



What Rubker Is 



India rubber or caoutchouc is an elastic substance that may 

 be derived from the milky juice of a considerable number of 

 different kinds of plants. Most plants about us have only a 

 watery sap; fruits such as the apple and our garden vegetables 

 like carrots, beets, etc., contain much water which comes from 

 the soil and is carried about in tlie plant as sap. But many 

 plants in addition to the watery sap have a milk-like juice. For 

 example when you pluck a leaf from a milkweed, spurge, or dog- 

 bane growing wild in and about New York City, a sticky milky- 

 white juice exudes. This is called latex and consists of an emul- 

 sion or physical mixture with numerous globules suspended in a 

 watery liquid. 



Suj:)pose you get a cup of this fn-sli latex and allow it to st.md. 

 The globules rise to the top quite as cream does on milk, and in 

 time a rather hard and solid layer is formed. This change of 



• .Abstract of a lecture given in the Central Display House of Conservatory 

 Range 2 on Satunlay afternoon, January 12, 1924. 



