VOL. X.] ' PHILOSOPHICAL TRANSACTIONS. 231 



that plant; such as those, that hold the turpentine and rosin in some trees; 

 there being as many several sorts of juices as there are species of plants, and 

 therefore peculiar vessels, preparing the last and proper juice for each respective 

 plant. 



The stems of trees and their branches increase by the external addition of h 

 new coat of fibres and air-pipes, growing about them every year, and thereby 

 giving them a new ring of wood. 



As to the knobs of plants, they are to our author nothing but the productions 

 of new offsprings upon a new implication of fibres and air-pipes, for the shooting 

 out of new leaves, and young sprouts or buds. 



A bud is, as it were, the new fcetus or birth of a plant, or a sprout contracted 

 in small, inclosing a tender woody part, (raised from ligneous fibres and medul- 

 lar bubbles) and the rudiments of the leaves; which being enlarged by the 

 moisture and warmth of the spring, extend themselves into the form of a sprout. 



The leaves are, to our author, a considerable part of the plant, seeing that all 

 those parts, that are wrapped up in the stem or trunk, do, when opened in the 

 extreme and younger parts, break out into leaves ; so that these seem to be 

 nothing but appendages to the trunk lengthened and opened; the ligneous pipes 

 and air-vessels, derived from the midst of the woody cylinder of the tender ring, 

 running together into a bundle, and forming the stalk, and at length upon their 

 dilatation completing the leaf. The great variety of leaves our author deduces 

 from the transverse ranks of bubbles appendant to the woody pipes of the stem, 

 upon the opening of the stalk. 



The office of the leaves seems to him very considerable, forasmuch as, in his 

 opinion, they perform the part of the skin in animals. They (the leaves) are 

 furnished with all the sorts of vessels to be met vvithin the body of plants, as 

 air-vessels, woody-fibres, and vessels >of transpiration. This opinion of his, viz. 

 that the nutritious juice is further concocted in the leaves, he endeavours to 

 render more probable by the consideration of the little seminal plant, which con- 

 tains two leaves ; insinuating also, that from the leaves there is a regress of the 

 concocted juice into the stem, and consequently a peculiar circulation. 



Esteeming the branches to be produced for the generation of the vegetable 

 €ggf he teaches, conformably thereunto, that a blossom or flower is, as it were, 

 the uterus together with the egg or fcetus of the plant, which in due season is 

 exposed to the air, to make it grow at length into a new offspring. In explaining 

 the manner of the production of flowers, and their variety, he is very curious; 

 as he also is in that of seeds; which latter he observes to be lodged in divers 

 cases or caskets, performing the office of an uterus and the parts thereof. And 

 seeing the seed grows in very many plants to an edible fruit, he describes the 



