294 THE SURVIVAL OF THE UNLIKE. [XVII. 



mate modifies plants are well known, — such as the 

 dwarfing of plants at the north, the tendency to fasti - 

 giate or strict forms of trees at the south, the shorten- 

 ing of the period of growth at the north, the develop- 

 ment of high colors of flowers and fruits and high 

 saccharine flavors at the north, the condensing of the 

 plant -body in arid regions, and the like. All these 

 and other changes which inure or adapt a plant to 

 climates at first injurious to it, belong to the general 

 subject of acclimatization.* There are only a very 

 few of these phenomena of acclimatization which di- 

 rectly interest the phenologist, — those which are con- 

 cerned with the visible modifications in seasons of 

 flowering, leafing, maturation of fruit, defoliation, and 

 the like ; and it is these features to which I wish, very 

 briefly, to call attention at this time, — not for the pur- 

 pose of making any scientific discussion of them, but 

 simply to aid the observer in taking more appreciative 

 records. 



It is generally considered that plants become annuals 

 or biennials as a result of adaptation to the environ- 

 ment in which they live. The interposition of a long 

 season of enforced inactivity causes the plant to store 

 up its energy for future use. This storage may be 

 made in the tissue of woody stems, in rhizomes and 

 roots, in bulbs, arid sometimes in seeds. When the 

 plant reduces itself to a bulb at the approach of the 

 dry or cold season, it thereby becomes a pseud -annual, 

 but when it reduces itself to a seed it is strictly annual. 



•For popular discussions of the acclimatization of plants, consult Crozier, 

 "The Modification of Plants by Climate." Ann Arbor, 1885: Bailey. "Accli- 

 matization: Docs it Occur?" (Essay XIX.); Pammel, "Climate and Plants," 

 Monthly Review of Iowa Weather and Crop Service, Oct. 1891. 



