REVIEWS. 
19 
developing the economic resources of our own country; 3rd, because the 
speculation— i.e., the substitution of home for foreign dye-stuffs—promises 
to be remunerative, as the rocellas have frequently reached the high price 
of £1,000 per ton in the London market. 
Dr. Lyndsay deserves our best thanks for the manner in which he has 
conducted these experiments, the result of which is given in twenty-four 
tables, attached to this pamphlet. If commanders of ships were aware of 
the value of these plants, which cover many a rocky coast and barren island, 
they might, with a slight expenditure of time and labour, bring home with 
them such a quantity of these insignificant-looking plants as would realize 
considerable sums to their own direct advantage, as well as that of the ship¬ 
owners, and, consequently, to the advantage of the State. 
The Flowering Plants and Ferns of Great Britain ; an attempt to 
classify them according to their Geognostic relations. By John Gilbert 
Baker. London: W. & F. G. Cash, 5, Bishopsgate-street Without. 
1855. 
In this pamphlet Mr. Baker developes, with much care, his views on a sub¬ 
ject of the highest interest to the botanist, viz., the relations of the plant 
to the soil on which it grows. So far as his generalization extends, we are 
inclined to agree with him ; but we believe that he has confined his atten¬ 
tion too exclusively to the mechanical condition of the soil, and neglected 
other elements which, in our judgment, are of even greater importance, as 
influencing the growth of particular species of plants; we mean the 
chemical constitution of the soil, and the height above the sea level and 
aspect. We shall allow Mr. Baker to introduce his own theory in his own 
words:— 
“ With reference to the facility with which they yield to disintegration and to 
their hygroscopicity and porosity (i. e. lithologically) strata are essentially separ¬ 
able into two principal classes, dysgeogenous and eugeogenous. 
u Dysgeogenous formations are those which are disintegrated with difficulty, and 
yield only a feeble detritus. On a grand scale they absorb moisture readily, and 
furnish stations characterized by their comparative dryness. Rocks of this class 
mostly contain a large proportion of carbonate of lime in their composition. 
“ Eugeogenous formations are those which abrade easily, and yield an abundant 
superficial detritus, Which may be either of a sandy or clayey nature. They are 
comparatively impermeable, and consequently hygroscopic upon a grand scale, 
furnishing damper stations than the rocks of the opposite category, especially 
when the detritus is clayey. 
u Every species possesses essentially its characteristic special range of lithological 
adaptability, in the same way that each possesses its characteristic special range of 
climatic adaptability. Under equal climatic conditions, some species are restricted 
