FAKMERS' INSTITUTES. 233 



bud, and tlieu the \yliole bud and food is enclosed within the protecting envel- 

 ope^ and in many cases, instead of the enveloping leaf remaining thin and folia- 

 ceons like the pea, it in some contiguous part becomes thickened and fleshy or 

 thickened and hard as in the pumpkin, apple, etc. In the case of the pea the 

 leaves containing the food are so distorted that tliey can never be of use as 

 leaves, and so do not come to the surface, while in others like the pumpkin they 

 not only appear above ground, but perform all the offices of a true leaf. In 

 other cases, like that of the beautiful climber, cobea scandens, the supply of 

 food is so limited that it is only with the greatest care that it can be started 

 from the seed, the plantlett starving to death before the necessary roots to col- 

 lect other food can be formed. We come now to the distribution of seeds, and 

 this subject is almost endless, for the seeds or fruit of almost every species is 

 specially adapted for distribution in some particular way. The means made 

 use of are, first, animals. Many seeds or fruits are provided with bristles or 

 awl-like projections wdiicli are barbed so as to prevent their being removed easily 

 from any thing they may penetrate. Sucli seeds attach themselves to the hair 

 of a passing animal, no matter how sleek tliey may be, and are carried long dis- 

 tances before they are dropped or brushed to the ground, thus distributing the 

 seed rapidly and efllectually. Burdocks, sticktight, and tory burrs are illustra- 

 tions. Other seeds are surrounded by a fleshy fruit which is the food of some 

 animal. In such cases the outer seed coat is usually hard and almost impervi- 

 ous to water, so that it can remain in the stomach and intestines while the 

 fleshy fruit is digested, and they are then voided unhurt in the excrement miles, 

 and in the case of migratory birds hundreds of miles away from the plant that 

 produced them. Many seeds of marsh plants are distributed by falling to the 

 earth and becoming mixed with the mud that adheres to the feet of some pass- 

 ing animal. The wind is the means for the distribution of the greatest number 

 of seeds, and very various are the arrangements to secure it. Some have a por- 

 tion of their outer coat split up into little hairs or down which make the whole 

 so buoyant that they float along on the lightest breeze. Others have broad 

 wings which sustain them, while still others have smaller wings, but so placed 

 that tlie seed can move downward only as a propeller wheel moves through the 

 water, and are thus sustained until drifted long distances, particularly as such 

 seeds are usually those of tall growing trees like the pine. Some seeds are 

 especially adapted for water transportation, and are surrounded by a light 

 spongy mass, which is enclosed by a thin, hard coat impervious to water. Such 

 seeds will float long distances, even from continent to continent, unhurt, and 

 when cast upon some island shore the outer covering gradually decays and 

 allows the w-ater to come in contact with the seed, which germinates and grows. 

 But plants are not always passively distributed. Many seed pods are so con- 

 structed that by the drying of some parts they burst open and scatter the seeds 

 in all directions. The wild touch-me-not and crane's bill of our section arc 

 illustrations, while the fruit of the Brazilian sand-box tree bursts open with a 

 noise equal to that of a pistol and scatter the seeds to a great distance. But to 

 return to the structure of the seeds. I have shown, or tried to show, that seeds 

 are not, as many farmers seem to regard them, simple inert matter, and although 

 it is necessary to add them to the soil to produce a crop, it is only so in the same 

 Avay that manure or water is necessary, but are living, although dormant parts 

 of the plant which produced them, and the fact that the parent plant, or rather 

 the balance of it, is dead does not affect their existence or their relation to it at 

 all, any more than the death of the original Baldwin apple affects the thousands 



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