328 On the Roots differing 171 each Soil. 



It is uncommonly thick, and the whole interior of the stem so 

 loose as not to be half filled, and the centre circle is a cylinder 

 of cotton curionsly formed: this I take (thongh so soft) to be the 

 wood part, as there is an interior line, small (but more solid in 

 matter ,1, on which all the branches of the root at e fixed, which 

 proves it to be the line of life, or canal vicduUairc. The ali>urnum 

 vessels, instead of being in their Jinial places (between the bark 

 and wood), are placed between the two rmds: and the inner bark 

 vessels follow. We may call the second rind a bark, for there 

 is 710 other: but if we do, it is still differently placed, since it 

 completely separates the seeds and iwrer bark lessrls: the pol- 

 len is as usual with tlie seeds, only the latter in vessels tied with 

 the string, and the farina in the spaces between them ; the two 

 rhids are more like leather. The wood (if it must be so called) 

 consists of soft cotton cvHadcrs filled with water, which 1 suppose 

 is taken up by the little pumps wliich are on the roots instead of 

 radicles: but there are /wo sorts; perhaps one of them takes 

 the juices for the seeds, and the other the uater, as there are 

 very few of (he former ; see fig. X, and fig XI; the water ones, 

 fig. XII, the shape of the wood vessels. The seeds are most 

 easily seen mounting the tree from the root in the stone pine, 

 and red spruce fir, as also in the semper viimms, if the two rinds 

 are divided. 



I shall now conclude this letter, and my next will be another 

 explanatory letter on the growth of the seeds in the root, show- 

 ing that they must be seeds, or at least the embryo or heart ; 

 since they are to be seen passing into the seed-vessel and fixing 

 themselves in the place of the seeds while the flowers are still in 

 the bud. 



I am, sir, 



Your obliged servant, 

 Sherwood; Jan, 99, 13 j 5. AgneS IbBETSON, 



A further Description of the Plate. 

 PI. VII. Fig. 1. Appearance of the radicles when dissected, 



Fig. 2. Form of the fibres only to be found in rich 



ground, trees and firs. 

 Fig. 3. The only sort of hairs found in the root. 

 Fig. 4, 4. The sort of roots common to all sand plants. 

 Fig. 5, 5. The quantity of radicles found in the root of 



the silver fir. 

 Fig. 6. The sort of root common to all water pla7its. 

 Fig. 7. Root common to clayey plants. 

 Fig. S. Roots common to many chalk plants. 



Fig. 



