THE AMERICAN BOTANIST 141 



during' the winter, and has not been seen since. How it came 

 there I cannot explain, as no other South African plant has 

 been found on this area. — Prof. J. C. Nelson, Salem, Oregon. 



Cold and Color. — It has often been noticed that at the 

 approach of cold weather, plants with red in their tissues tend 

 to deepen in color. During a cool spring, even white flowers 

 incline to a rosy tinge and plants with ordinary pink or pinkish 

 flowers take on a more vivid tone. The red hues in flowers 

 are almost always produced by a substance called anthocyanin 

 which occurs in plants combined as a glucoside. Glucosides 

 are substances which may be split up into sugar and some other 

 substance. Thus chromogen split from a glucoside forms 

 anthocyanin by oxidation. It is well known that cool weather 

 checks the formation of starch and causes the food made by 

 plants to accumulate in the form of sugar. A cool spring, 

 therefore, makes more color in plants by causing an excess of 

 sugar with the consequent formation of more anthocyanin. The 

 same effects are caused by the increasing coolness of autumn 

 days. 



The Sycamore. — There are two species in our flora in- 

 correctly called sycamore. One of these is the Norway maple 

 {Acer psciidoplatanus) and the other is the buttonwood {Pla- 

 tanus occidentalism . The true sycamore which a certain biblical 

 character, Zaccheus, is said to have climbed, is a fig (Ficus 

 sycamorus) . A number of fig trees have pahnately-veined or 

 plamately-lobed leaves and it is quite likely that our misnamed 

 trees received their appellations from a fancied resemblance of 

 their leaves to those of the true sycamore. In the early days 

 of botany, it was customary to consider the European plants 

 identical with those described from the Levant, by the Greeks 

 and other early writers and many incongruities in plant names 

 may be traced to such sources. We may get a hint of how 

 frequently one plant was named for its resemblance to 

 another by noting that the specific name of the Norway maple 

 (platanoidcs) means resembling a plane tree (Platanus) . 



