Dr. Smith's Inquiry into the Structure of Seeds. 211 



begin to rise above ground, is found to cramp the subsequent 

 growth of the plant. The oil of the Cotyledons has been usually 

 supposed a protection to their internal parts, I presume against 

 wet : but this purpose it by no means does or can answer, for all 

 seeds readily absorb moisture whenever they meet with it, and, 

 if likewise exposed to the action of oxygen, they vegetate, in 

 whatever situation they may otherwise happen to be. I suspect 

 moreover that the oily and mucilaginous fluids of seeds in gene- 

 ral, before they perform their office in germination, all previous- 

 ly become milky, and often saccharine, from the actions of wa- 

 ter and oxygen. It might be worth while to inquire, whether 

 exposure of such seeds as are most prone to turn rancid, to a 

 quantity of oxygen, would tend to preserve them- It is, I be- 

 lieve, found that the admission of some atmospheric air is ne- 

 cessary to the preservation of many seeds. The primary cause 

 of decay therefore in seeds spoiled by keeping may originate, 

 not, as I have supposed, in the extinction of their vital princi- 

 ple, but in the corruption of their albuminous oils.; and this is 

 strengthened by the experiments of the French chemists, whose 

 applications may much more readily be supposed to correct and 

 restore the albuminous juices, than to bring the dead to life. 



This idea of the albuminous matter, whether oily, mucilagi- 

 nous or farinaceous, being, when not a distinct and separate 

 body, always lodged in the Cotyledons, throws additional light 

 on the nature of the last-mentioned parts, and in a very beauti- 

 ful manner confirms their analogy with leaves. The discoveries 

 of Mr. Knight have proved that the nutritious fluid or sap of 

 plants is carried into the leaves, in order to be there acted upon 

 by air, light, heat and moisture. After these agents have pro- 

 duced their effects, the fluids are sent back, through the return- 

 ing vessels, into the branch or stem, to furnish matter of increase 



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