4*24 Affinities between Plants 



Ay^. 'tfflKW^ and'W- 



jacent Rocks. By Mr. Hewett C. Watson. 



The various attempts made by different writers in this 

 Magazine with a view to prove or disprove a direct con- 

 nection between the geology and botany, or between the 

 rocks and vegetation, of particular districts in Britain, have, 

 doubtless, been read by many with considerable interest; but, 

 as yet, it must be confessed that very little appears to have 

 been effected with regard to a settlement of the point mooted. 

 Some botanists have pronounced the attempt at tracing such 

 connection to be utterly hopeless ; while others see, or fancy 

 that they see, the most palpable and positive evidence in 

 proof thereof. In the fullest sense of the term, indeed, geo- 

 logy is intimately connected with botany ; but, in saying this, 

 it is to be understood that the form, structure, and elevation 

 of countries are all taken into consideration. Neglecting 

 these, and looking only to the comparative age and minera- 

 logical character of the rocks, so far as a very slight acquaint- 

 ance with these matters authorises an opinion, it would, on 

 my own part, be adverse to the existence of any except very 

 feeble affinities. Throughout nature, the secondary or 

 weaker influences are so frequently overshadowed by others 

 more powerful, the feeble are so very often held in abeyance 

 by the stronger affinities, that hasty or partial observations 

 continually lead us to opposite opinions; and, in perusing 

 some of the recent essays and remarks on the connections 

 between rocks and plants, we can scarcely avoid the sus- 

 picion that something of this kind has at times caused the 

 difference of belief in regard thereto. How often do we find 

 the mechanical properties of bodies interfere with, and pre- 

 vent the due display of, their chemical action on each other ! 

 How frequently does one powerfully excited passion control 

 and conceal all feebler tastes and feelings ! How common is 

 it for a man at one time to appear proof against some con- 

 tagious disease, to which, at another period, his frame yields 

 with a facility altogether inexplicable ! Partial observation 

 has hence drawn the axiom, that " exceptions may be found 

 to every rule,'' save this supposed rule itself; whereas the 

 very idea of an exception to a law of nature is an utter 

 absurdity ; the apparent exceptions being only examples of 

 another law more forcible in its sway, and capable of control- 

 ling, but not changing or destroying, the feebler one. It is 

 thus necessary that all conditions of vegetable distribution be 

 studied in connection. He who neglects any, will so far fail 

 in his generalisations. In illustration of this, I propose to 

 give, as briefly as can be 5 the. general results of my own 

 observations on the affinities between rocks and plants. Pre- 



