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Notice of * Outlines of Structural and Physiological Botany. By 

 Arthur Henfrey, F.L.S., &c.' Part II., Organs of Vegeta- 

 tion. 



The second part of this useful little book fully bears out our re- 

 marks on the^rs^ In that notice we confined ourselves to a general 

 expression of approval without giving examples of the author's la- 

 bours, an omission which we shall now supply, premising that what 

 may be wanting in the novelty of the passages we shall cite is abun- 

 dantly compensated by the lucid arrangement of the matter. The 

 chapter commencing this partis entitled "The Individual Plant," and 

 the section which we cite " Morphological Considerations." 



" In a former chapter it was stated that certain plants consist of a 

 simple cell, and that all plants make their first appearance under that 

 form ; it is only at the extreme limit of the vegetable kingdom, how- 

 ever, that they remain in such a simple condition. The primary cell 

 divides, but as an evidence of an advance in the scale of organization, 

 these cells do not become independent of each other; on the con- 

 trary, remaining attached, they subdivide again and again, till we find 

 individual plants composed of an innumerable mass of such cells. 

 The plant thus begins to acquire parts or organs destined to perform 

 fiinctions distinct from each other, and subservient to the general nu- 

 trition and propagation of the whole. 



" Looking at vegetables in their generality, we may say that a plant 

 consists of three parts, the leaf, the stem, and the root ; although in 

 the lower classes it is often the case that one or even two of these are 

 wanting. Advancing again, as in the case of the cell, we find that a 

 plant may be composed of one of these individuals, or phytons as 

 they have been called, producing its like, the progeny immediately 

 obtaining an independent existence ; or the new individuals may re- 

 main attached almost to an unlimited extent, constituting highly com- 

 pound plants, the difierent organs or phytons of which undergo vari- 

 ous modifications of form and acquire very distinct functions. Thus 

 in a flowering plant, or, as a stronger example, in a forest tree, every 

 leaf is to be considered as essentially a distinct individual ; but as a 

 member of a compound body, working for the general benefit of the 

 whole. In obedience to the requirements of this, they undergo mo- 

 difications to fit them to execute distinct oflSces in the economy of 

 the plant ; some are destined to the nutritive functions, others to the 

 reproductive ; and among these latter we find them still further losing 

 Vol. II. 4 E 



