DECLINE OF PLANTS. 



efficient state of the feeding organs, the plant is unequal to the task of absorbing and as- 

 similating the same amount of food as in its youth; herein there is obviously a great sim- 

 ilarity between plants and animals. I believe it is equally certain, that a structural change 

 does gradually occur in plants, as well as in animals, when an individual declines in 

 vigor, which change cannot be attributed solely to the action of external agents. 



I may again quote the observation of the Editor of the Irish Farmers' Magazine, re- 

 specting the gradual changes induced by age, in the quality and productiveness of a vari- 

 ety of potato. " In a few years after a variety has been raised from seed, it arrives at its 

 greatest degree of productiveness; then it continues annually, for a number of years, to 

 decrease in productiveness, but to become more valuable for food, being more farinaceous, 

 or as it is termed drier; afterwards it begins to lose this quality, also, and rapidly to de- 

 cline, until in a few years more, it is utterly useless." Similar observations occur in the 

 tenth vol. of the Quarterly Journal of Agriculture. In vigorous growing, productive va- 

 rieties of the potato, yielding at first coarse grained tubers, so full of fluid sap as only to 

 be fit for cattle, this progressive change in the quality, and consequently in the composi- 

 tion or structure of the tuber, has been frequently observed. Holt, in the Transactions 

 of the Society of Arts, mentions a variety called the " Dabb," large, coarse, and strong 

 flavored, and therefore unsuited for the table, which became so much improved as to be no 

 longer rejected. Martin Doyle, in his Cyclopgedia of Agriculture, observes, that " the 

 Irish Lumper is becoming every year more farinaceous and palatable." Other observa- 

 tions to the same effect, may be found in papers on the "blight" of the potato, published 

 by the Highland Society of Scotland. A remarkable change in the character of a valua- 

 variety, came under my own notice. In my youth, a large red, kidney shaped potato, 

 known as the Scotch Red, or Flat Red, was most extensively cultivated, and almost uni- 

 versally esteemed, in consequence of its being very white and farinaceous when cooked. 

 Having been from home a few years, I found on my return, a potato in use of very inferi- 

 or quality — soft, watery, and of a yellow color, and was surprised to learn that this was 

 the Scotch Red, which was formerly so excellent. On going through the grounds of a 

 market gardener, soon after, a patch of potatoes with peculiar spindling stems, and scanty 

 foliage, attracted my attention, and on inquiring the name of the variet3', I learned that 

 it was the Scotch Red; it had been so great a favorite, my friend remarked, that they were 

 obliged to continue to grow a few, as some people would have them, but they could no 

 longer rely upon it for a crop; many sets perished without vegetating, and it was now com- 

 paratively unproductive, and the potato worthless. 



The quality or dry condition of the tubers of a given variety, may be influenced to a 

 certain extent, by the nature of the soil and season; but the gradual alteration in the tu- 

 bers of varieties, as above stated, is certainly of too general and progressive a character to 

 be the exclusive result of any external influence; it is manifestly a consequence of the 

 declining power of the inherent principle of life. 



The change from a coarse, watery potato, fit only for cattle, to one so different as to be 

 suitable for the food of man, is an event of too marked a character to pass unnoticed, even 

 by the most careless; hence this change has been more particularly noticed in such varie- 

 ties. But if coarse varieties of the potato are subject to this progressive change, is it not 

 probable that all are governed by the same law; that the finer varieties must be similarly 

 affected; may not those which from the first were comparatively dry and farinaceous, be- 

 come in the course of time, and when growing under ordinary circumstances, still drier, 

 fluids thicker, and less abundant. If this be so, then it is no longer a mystery why 

 or old age never fails to bring on the curled or shrivelled disorder;" why a variety 



