1907] How THE Seeds of Plants are Spread 27 



HOW THE SEEDS OF PLANTS ARE SPREAD IN 



NATURE. 



By Norman Griddle, Awerne, Man. 



In the common natural objects about us there is an endless 

 field for Nature Study. So vast indeed that the difficulty would 

 be not in seeking a subject, but rather in selecting from the 

 abundant material at hand one that is both interesting and in- 

 structive, and is at the same time not too difficult for the beginner 

 to understand. 



The remarkable though simple methods adopted by the 

 different plants for the propagation of their kind, in so many 

 cases very dissimilar, should be known to every one, and, for a 

 Nature Study, form excellent subjects both for observation and 

 deduction, to say nothing of the interest they might awaken 

 and the pleasure they might give to any one making a study of 

 the subject. In this paper I shall try to treat part of this subject 

 -under the above heading. 



Before going into details it may be well to state for the 

 benefit of the beginner, that every species of plant, however 

 simple or complex its structure may be, is specially adapted 

 for its advantage in the struggle for existence ; and that however 

 much one genus may vary from another in essential particulars, 

 the object is always the same. Namely, to multiply to the utmost 

 limit. A student, therefore, W'hen examining a plant, should bear 

 in mind that whatever the structure, it is for the plant's benefit, 

 and that it has maintained the species in the struggle with other 

 plants and with animals, for a number of centuries. There is in 

 fact a reason for every detail. 



I. Seeds that are Carried by Wind. 



Seeds under this heading always have attached to them 

 some fluffy material to catch the wind, like the pappus of the 

 dandelion, or they are winged like the vSeeds of maples and 

 conifers. The common dandelion and other close allies offer 

 simple objects for study, as some form can be found nearly 

 everywhere. The seeds of this plant, as the pappus shows, de- 

 pend almost entirely on the wind for transportation and migra- 

 tion. In many instances the pappus undoubtedl}^ enables them 

 to travel several miles. There is, however, a condition that is 

 absolutely necessary. The plant will not let the seeds go in damp 

 or wet weather, and if the air becomes damp while the seeds are 

 travelling, they soon drop to the ground. This applies to all the 

 fluffy seeds and in a lesser extent to the winged kinds. The 



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