60S Lindley's Nixus Plantarum. 



Jolianne Lindley, Phil. Doct., Professore Londinensi, Auc- 



tore: Nixus Plantarum. (Approximations of Plants). 



MDCCCXXXIir. Londini, apud Ridgway et Filios. 



8vo, paginae xxiv. 



Those of the students of the natural affinities of plants who 

 are familiar with Latin, will find this work one of high in- 

 terest and real value to them. As premonitory to its scope 

 and office we present the following extract from the same 

 author's Introduction to the Natural System of Botany^ 

 p. xvii. : — 



" As plants resemble each other more or less in a multitude 

 of different respects, it is impossible to indicate all their affi- 

 nities in a lineal arrangement. The consequence of this is that 

 while the orders themselves are really natural, the same title 

 often cannot be applied to the arrangement of them in masses. 

 For example, CupuliferjE and ^etulineas are obviously con- 

 nected by the most intimate relationship, and, as collections 

 of species, each of them is perfectly natural; yet one of them 

 stands among apetalous plants, the other among achlamydeous 

 ones ; hence the two latter groups are artificial. In fact, it 

 appears from what we at present know, that no large combin- 

 ations of orders are natural which are not founded upon ana- 

 tomical differences; thus Cellulares and Vasculares, Exogenae 

 and Endogenae, Gymnospermous and Angiospermous Dicoty- 

 ledons, are natural divisions; but Apetalae, Polypetalae, 

 Achlamydese, and all their subordinate sections, are entirely 

 artificial." 



" Characters which are purely physiological, that is to say, 

 which depend upon differences of internal structure, are of 

 much more value than varieties of form, position, number, 

 and the like, which are mere modifications of external organs." 



In the present Nixus Plantarum the author illustrates 

 more fully the ideas committed to notice in the above quo- 

 tations ; and instances several incongruities which have been 

 introduced into published systems of natural affinities by too 

 great a dependence on characters not physiological, especially 

 those derived from the hypogynous, perigynous, and epi- 

 gynous position of the stamens. The author conceives that, 

 by the application of the physiological characters, with the 

 subordinate aid of the analogies which may occur in the con- 

 tingent ones, the orders may be hereafter profitably and 

 satisfactorily distributed into sections ; an event which would 

 facilitate the acquisition of a knowledge of plants when 

 studied by their natural affinities. 



The exhibition of these tendencies or bearings in the 

 received orders or groups of plants is the business of the 



