I 



L 



On the Physiology of Vegelalles. 407 



so. Nor can perspiration be more incompaUbJe to the form 

 and very vature of a vegetable. No cold-blooded animal per- 

 spires, anrl plants niav be considered in this light : a being whose 

 juices never rise 10 or 13° above atmospheric heat, and whose 

 blood, and that for a verv short time, rarely deviates from it, 

 may be called a cold-blooded being; and can neier require that 

 perspiration necessary to cool and regulate the heat of the sy- 

 stem. The uses of perspiration are to free the blood from its 

 redundant water, — an operation 7;e£fe^c//7f 5 ceitainly cannot re- 

 cjuire, — and to expel from the body those particles which by re- 

 peated circulation have become acrimnnioif^. Now I have s-hown 

 before that plants have no circulation, of course they require 

 not this reduction. 



But before I close this letter, I must add, that I have liad 

 fresh proofs of the growth of the flowers on the glass ; cutting 

 seeds both iiefore and after impregnation. The Jlowe<s (when 

 the piece of the seed has been left on the glass) have spread in 

 almost every instance entirelv all round it, — in one specimen at 

 more than a quarter of an inch distance, in various patterns ; and 

 that in two of the fir seeds, taken from the root, patterns have 

 been prolonged evidently from the corculum of the seed, (See 

 fig. 7. and fig. 8.) 



But I shall no further extend this letter, but leave to the 

 opinion of my readers and botanists in general, whether the 

 foundation of botany is not now so thoroughly delineated, that, 

 without repeating every circumstance before discovered, I may 

 without further prelmie dedicate n)y future time to the consi- 

 deration of the detail of vegetables, till I shall be able to lay the 

 whole in one regular picture before the public, which I live 

 but in the hopes of doing. Every link of the chain is now com- 

 plete, every division filled up. Tliis last discovery finishes the 

 foundation, and renders it as perfect as human delineation ad- 

 mits, and as constant dissection and extreme labour will allow. 



I am, sir, 

 Your obliged humble servant, 

 Exeter, Nov. <2, 18 !G. AgNES IbBKTSON. 



Description of the Plate No.4, [see PI. V.] 



Fig. 1. A diminutive specimen of the part of the bean sur- 

 rounding the embryo. 



Fig. 2. The seed of the melon just after fructification. 



Fig. 3. The seed of the buckwheat taken round the embryo. 



Fig. 4. The interior of the large pea, a small specimen pre- 

 ceding fructification. 



Fig. 5. Specimens of the heart of the fir seed, now round, 



tjjough afterwards u long oval; taken while in the root, before 



C c 1 they 



