16 



THE AMERICAN BOTANIST, 



tioti has shown, however, that no matter in what soil the 

 plants grow, those in deep shade are the ones HkeHest to 

 turn blue and the lack of light is the theory now advanced 

 for the change in color. Possibly this may have some 

 bearing on the fact that the flowers of autumn when the 

 light is not strong are principally of some shade of blue or 

 violet, 



Japanese Fern Balls— In the Fern Bulletin for Octo- 

 ber, Kiichi Miyake notes that ferns are rarely cultivated 

 in pots in Japanese households, fern balls, made by twin- 

 ing the flexible rootstocks of certain species, taking their 

 places. These balls are now becoming common in Amer- 

 ican conservatories, also. The plant from which they are 

 made is DavalHa buUata. It formerly abounded in the 

 mountains of Japan but is not common there now because 

 constantly sought for decorative purposes. A writer in 

 the Garden asserts that DavalHa Mariesi is also used for 

 these fern balls. It has slenderer rhizomes with silvery 

 white scales changing to gray. Both species make good 

 pot plants and are easily raised from .spores. 



Color and Evolution, — In the present age no one will 

 seriously deny that evolution has played an important 

 part in the development of plant and animal life; but 

 when we try to interpret every feature as the direct out- 

 come of the struggle for existence, we are probably far 

 from the truth. We assume that fruits have attractive 

 colors and pleasing flavors in order that birds and other 

 animals will carry them off for food, and so disseminate 

 the seed ; but the rule has many exceptions. What ani- 

 mal eats the berries of the winter-berry {Ilex verticillata) 

 except under stress of hunger, or those of the bittersweet? 

 And yet our winter fields and swamps show no colors 

 more brilliant than are worn by these fruits. Where are 

 the animals that developed these colors from among the 

 primitive berries of a more sober hue ? And what palate 

 assisted in the evolution of the winter-berry's nauseous 

 taste ? Or that of the spice-wood ? The berries of the 

 twisted stalk (Streptopus roseus) hang on the stalks un- 



