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nature, and so capable of being continued and further devel- 

 oped in domestication, it is not difficult to imagine. Our 

 authors perhaps, in common with naturalists generally, do not 

 sufficiently recognize the natural tendency to perpetuation of 

 individual characteristics. 



As regards ordinary variation between different individuals 

 of the same species, the want of due consideration of what 

 every good observer knows to be true, has indeed " mainly 

 contributed to such an undue multiplication of species in the 

 vegetable kingdom as botanists unfamiliar with large herbaria 

 and exotic plants are slow to believe, and to the exaggerated 

 estimates of the supposed known extent of the vegetable crea- 

 tion that gain common credence." Our authors believe that 

 the number is swelled one third beyond its due extent by the 

 introduction of bad species founded on habit, and on acci- 

 dental variations produced by soil, exposure, etc. ; and, we 

 would add, on the imperfection of the materials from which 

 the greater part of the species that crowd our books were 

 originally described, most of them without due elaboration of 

 already published species, and drawing after them an ever 

 lengthening train of nominal species, founded on mere guesses 

 at supposed differences from vague and incomplete descrip- 

 tions, without any collection of specimens. 



We have already exceeded our limits, while yet at the 

 beginning of Drs. Hooker and Thomson's interesting and 

 suggestive volume. AYe regret that we must omit all notice 

 of their remarks upon habit as indicating specific difference, 

 which, contrary to the general view, they regard as " most 

 deceptive," and must pass over their important section 

 upon geographical distribution in general, and its dependence 

 upon specific centres. We only add, that whoever would 

 attain a clear comprehension of the configuration, the diverse 

 climates, and the general botanical geography of those exten- 

 sive and widely varied regions which are comprised, and in 

 most minds confused, under the general name of India, has 

 only to study the admirable sections on the meteorology of 

 India, and on the physical features and vegetation of its 

 provinces, which occupy a large portion of the Introductory 



