Oct. 31, 1872] 



NATURE 



531 



and then only discharge their pollen in the' immediate I 

 proximity of the female flower ; after which the stalk of 

 the female flower again coils up, and carries it down to 

 the bottom of the water, where the seed ripens. 



The second part, on " Classification of Plants," is occu- 

 pied with a brief description of the various systems 

 adopted at diff'erent stages of botanical knowledge, with 

 short biographies and portraits of the most distinguished 1 

 botanists, from Tournefort to Robert Brown. 1 



The third part is devoted to the " Systematic Arrange- 

 ment of Plants," commencing from the lowest and pro- 

 ceeding to the highest forms. The account of the different 

 orders of flowerless plants is the best with which we are 

 acquainted in any elementary work, and will give the 

 beginner an excellent outline of the immense variety of 

 structure and physiological phenomena to be found among 

 the lower forms of vegetable life. We find a good de- 

 scription of the different modes of reproduction in the 



PS 



Alga:, which arc often so enveloped in technical terms as 

 to be barely intelligible to the student. The illustrations 

 also are excellent, as is the case throughout this section. 

 Those here given of the early stages in the life of a fern 

 taken from Thuret (Figs. 3 — 7), are such as have been 

 heretofore unknown to English text-books. This sec- 

 tion is, in fact, altogether thoroughly satisfactory. 



More exception may be taksn to the portion which 



VaUisnerja spiralis 



notwithstanding its defects ackno .vledged by the author, 

 of the unsatisfactory system of classification adopted by 

 Lindley in his " Vegetable Kingdom." The retention at 

 the present day of such classes as the Rhizogens and 

 Dictyogens as of the same value as Monocotyledons and 

 Dicotyledons, is altogether indefensible. An equally 

 serious defect is the very inadequate amount of attention 

 given to the Gymnogens, and to the elucidation of the 



treats of flowering plants, especially to the continued use, ' peculiarities of their structure which seem to form a con- 



