INDEX SECOND. 



Petit Thouarsy his theory of the origin of wood, 352. 



of the divergent layers, 353. 



Phaseolus vulgaris, structure of its petiole, 577. 

 Physiognomy of plants, importance of attendingto it, 255. 

 Phytology, definition of, 2. 

 Pith, its characters, 366'. 



causes which form its cells into hexagons, 372. 



its use to the plant, 374. 



is not the vegetable brain, 374. 



Mr. Knight's experiments on it, 375. 



new theory of its use, 377. 



is never obliterated in a sound stem, 380. 



- is never converted into wood, 381. 

 Plant, definition of, 2. 



Plants, bulbiferous, seldom ripen their seeds, 458. 



tubei iferous, change their place in the ground, 152. 



i vital functions of, 50. 



1- consequences of propagating those from warm climates by slips, 450. 



Platanus oriental, its gems are latent during summer, 460. 



Pliny, his limited knowledge of plants, 8. 



Poa trivialis, its cuticular meshes, 6'05. 



Polypi, how they are nourished, 48. 



Potatoe, when brought to Europe, 27. 



Prickle, its structure, 651. 



Progeny, lateral, is merely an extension of the parent. 449. 



Proper juice, the vegetable blood, 116. 



is sometimes coloured, 117. 



effects of the air on, 118. 



' cannot be procured quite pure, 119. 



. supposed to contain globules, 119. 



elementary principles of, 121. 



Pubescence is changed by climate and soil, 504, 645. 

 kinds of, 638, 647. 



- affords specific distinctions, 645. 



Pyrites, iron, in large quantity is injurious in soils, 215. 



R. 



Radicles have no medulla, 408. 



in the root originate from the medullary sheath, 409. 



in a branch laid down, spring from the alburnum, 409. 



always form a right angle with the part whence they issue, 4 1 0. 



Radishes, how to produce them early and large, 135. 



Radix filipendula, mistake regarding it, 143. 



Rafn imagined he had detected globules in the proper juice, 119. 



Raleigh, Sir Walter, did not bring the Potatoe to Europe, 27. 



Ranunculus aquatilis has two kinds of leaves, 608. 



Ray, John, his character as a Botanist, 1 1 . 



Resin, its components, 123. 



Rhododendron punctatum, structure of its foliar glands, 634. 



Roots are not nutritious organs in all plants, 127. 



filipendulous, not to be confounded with tuberiferous, 143. 



appendages of, 144. 



in some instances absorb nutriment from the air, 190. 



.. some change their place, 193. 



their direction always opposite to that of rootlets, 195. 



may be produced on the stem and branches, 198. 



VOL. I. Z Z 



