REVIEWS. 235 



garden, or to the beauty of the wild flowers of our fields and woods, 

 or those with which culture adorns the parterre or the green-house. 

 Many feel the desire occasionally to make them the subject of scien- 

 tific study, but they are met by difficulties which discourage and 

 repel all but the most persevering ; and which oblige even these to be 

 satisfied with becoming acquainted with a certain number of objects 

 without forming any clear idea of an order of nature among the sub- 

 jects of their study, or of the well-distinguished groups which make 

 up the whole. Since a professedly natural method has been generally 

 adopted, the genera have undoubtedly been collected into those 

 higher families which among plants are, by an improper application 

 of that term (inconsistent, at least, with its use in other parts of 

 Natural Science), called Orders ; but, although much is thus gained, 

 these families have not always characters easily recognised by the stu- 

 dent ; and higher com.binations, presenting distinctly to the mind larger 

 associations, are absolutely essential to our enjoying the advantages 

 of good classification. So far as concerns the highest divisions of all, 

 we cannot but think that Jussieu's AcotyledoneEe, Monocotyledonese, 

 and Dicotyledonese, exhaust the subject, and are so well supported by 

 every part of vegetable structure, that we may rest on them with full 

 satisfaction ; but it is, at the same time, clear to us that they are not 

 classes in the sense in which it is convenient to use that term in 

 Natural Science, but what in Zoology are called sub-kingdoms or 

 oranches, and that the other proposed classes, if good at all, are such 

 sections of these sub-kingdoms as ought to be called classes ; but the 

 difficulty is that, between the sub-kingdoms and the great families 

 which it is customary to call orders, we need and have not yet ob- 

 tained such good divisions, conformable to nature and separated by 

 well-marked characters, as might with propriety take this name. 

 The Gymnospermous Exogens may be a good class of Dicotyledoneee 

 (for the structure is Dicotyledonous, though the cotyledons are more 

 than two) ; and it is possible, though less clearly made out, that 

 • Lindley's Dictyogens may be a good class of Monocotyledoneae (of 

 its members being within that sub-kingdom there can be no doubt) ; 

 but there remains in each sub-kingdom a great assemblage of families 

 which must aiford means for establishing good divisions of equal im- 

 portance with these, though such divisions have not yet been de- 

 tected. In what he calls alliances, Dr. Lindley made an admirable 

 attempt, making the best use of what had been done by others, and 



