THE AMERICAN BOTANIST. 



17 



gatliered and finallj^ drop to the earth below. It would 

 seem, that manj^ colors are merely of secondary conse- 

 quence. Otherwise, why is a beet root red and that of the 

 carrot orange and yellow ? The sap of most plants is 

 colorksSo Why was white sap necessary to the poppy's 

 evolution^ or orange-colored sap to the celandine^ s, or red 

 sap to the bloodroot's ? 



Gum Arabic. — This gum, best known for its use as 

 mucilage, is the product of various species -of Acacia. 

 There is considerable difference in the color and adhesive- 

 ness of the gum from different species, that from Acacia 

 Arabica being considered the best» 



Uses for White Birch Timber.— According to Fores- 

 try and Irrigation more than thirty-five million feet of 

 white birch timber ar-e annually taken from forests in the 

 State of Maine. This is used principally in making hard- 

 wood novelties and in the manulacture of spools. Of the 

 latter^ about eight hundred million are turned out each 

 year. 



A Bat Country Life in America, for Januarj- 



gives a photograph of a little red bat that had been 

 •caught by the common burdock, and mentions other in- 

 stances in which this animal h as fallen victim to the plant. 

 In one case the bat was fotmd on the ground beneath the 

 plant, still alive but so covered with burs that it could 

 hardly move. 



Germination of Pollen Grains.— Pollen grains, it is 

 said, may be artificially germinated in water, or in water 

 to which a little sugar has been added. A French scien- 

 tist who has been experimenting in this line asserts that 

 some pollen grains that do not readily germinate in water 

 may be easily induced to do so by adding to the water the 

 stigmas of the same or allied plants ; from which he draws 

 the inference that there must be in the stigma certain sub- 

 stances that induce germination of pollen from the same 

 species and prevent it in foreign pollen. 



