ON THE INTERIOR OF PLANTS. g^l 



closer, sometimes adding a small fiece . to the interior, for 

 the puroosc of collecting iiourisbrnent. Tiere is, however, 

 a sort of h How plant, which fornv" a complete stoppage ; 

 but it generally grows in wet ground; and will be noticed 

 with water plants, in another letter. These varions differ- 

 ences very exactly regulate many important points belong- 

 ing to the construction of the interior of tlie stem, viz. the 

 quantity of new formed wood; the situation, manner of 

 passing, and regulation of the buds ; and particularly the 

 formation of the minor obstruction, which I shall now 

 explain. 



This last seems more particularly to belong to those plants, M?nor ob- 

 which, without stopping the pith, a little impede its prot^ress; J^'^uctioa. 

 and the curious construction of which is such, that, had I stoppage of 

 not already shown it in the French bean, 1 should have de- ^^ P'^^* 

 ferred mentioning it here, till better able to comprehend its 

 Mructure. 1 have found the marks which indicate the aper- 

 ture in the largest trees. In the Weymouth pine, and in 

 the silver fir, it seldom fails to give proofs of its excentri- 

 city, even at the exterior of the tree; but I never saw the 

 ball, except in those which are running plants, or at least 

 shaped like them; that is, that have the large shooting 

 branches made like the shoulder of a man, with a ball and 

 socket*. I at first conceived, that in these small plants the 

 branches were to turn on the ball ; but 1 have found many 

 specimens, where the limb was too firmly fix'd for this pur- 

 pose. I then conceived it the foundation for tendrils; but I 

 -have found it where no tendrils are : besides, it is too dimi- 

 i^utive. Not able to dedicate more than one figure to this 

 service, I must delay many extraordinary proofs of its ex- 

 istence; and mHny curious peculiarities of its structure, on 

 account of the buds, which demand all the sketches I can 

 venture to give. I shall only say therefore, that it is fixed in 

 ,tbe under part of the branch, where no bud ever comes, but 

 ^s defended with the greatest care.-^(See PI. IX, fig. l.)t 



* I understand that I have been thought to commit my self in comparing" 

 a part of the seed to the breast of a bitch, havintr riisapproved at animal 

 comparisons ; but it -vras a long analogs i found fault with, not a bimple 

 likeneiss in form , and surely there it a j^reat difference between such a 

 . one, and an analogy reaching to perspiration, circulation, and even per- 

 ception 

 f This, with some other figutei belonging to ihe present paper, ii ob- 



In 



