Bailey.] -^-^^ [May 1, 



them are true perennials in their native liomes. These plants are, with 

 us, plur-annuals, and amongst them are the tomato, red pepper, eggplant, 

 potato, castor bean, cotton, Lima bean and many others. But there are 

 some varieties of potatoes and other plants which have now developed into 

 true annuals, normally completing their entire growth before the approach 

 of frost. It is all the result of adaptation to climate, and essentially the 

 same phenomenon is the development of the annual and biennal flora of 

 the earth from the perennial. An interesting example of the eflFect of 

 climate upon the seasonal duration of plants is the indeterminate or pro- 

 longed growth of plants in England as compared with the same plants in 

 America. The cooler summer and very gradual approach of winter in 

 England develop a late and indefinite maturity of the season's growth. 

 When English plants are grown in America, they usually grow until 

 killed by fall frosts ; but after a few generations of plants, they acquire 

 the quick and decisive habit of ripening which is so characteristic of our 

 vegetation. I once made an extended test of onions from English and 

 American seeds (Bull. 31, Mich. Agric. College), and was astonished to 

 find that nearly all of the English varieties continued to grow until frost 

 and failed "to bottom," whilst our domestic varieties ripened up in ad- 

 vance of freezing weather. This was true even of the Yellow Danvers 

 and Red Wethersfield, varieties of American origin and which could not 

 have been grown very many years in England. Every horticulturist of 

 much experience must have noticed similar unmistakable influences of 

 climate upon the duration of plants. 



A most interesting type of examples of the quick influence of climate 

 upon plants — not only upon their duration but upon habit and structural 

 characters— is that associated with the growing of "stock seed" by 

 seedsmen. Because of uncertainties of weather in the Eastern States, it 

 is now the practice to grow seeds of onions, Lima beans and other plants 

 in California or other warm regions ; but the plants so readily acquire the 

 habit of long-continuing growth as to be thereafter grown with dilficully 

 in the Northeastern States. It is, therefore, necessarj' tliat the seedsman 

 shall raise his stock seed every year in his own geographical region, and 

 this seed is each year sent to California for the growing of the commer- 

 cial seed crop. In other words, the seed of California-grown onions is 

 sold only for the purpose of growing onion bulbs for market, and is not 

 planted for the raising of a successive crop of seed. This results in grow- 

 ing only a single generation of the crop in the warm country. Onion seed 

 from stock which has been grown in California for several years pro- 

 duces onions which do not "bottom" well, much as I found to be the 

 case with the English onion seed. 



But many plants, in geologic time, could not thus shorten up their life- 

 history to adjust themselves to the oncoming of tlie seasons. They 

 ceased their labors with the approach of the cold or the dry, tucked up 

 their tender tissues in buds and resigned themselves to the elements. If 

 a man could have stood amongst those giant mosses and fern forests of 



