114 Bibliographical Notices. 



are highly specialized, the general structure retains, more or less, the 

 primitive community of function which originally characterized it." 

 We have seen that in the simplest or most homogeneous beings the 

 entire surface participates equally in the function of absorption, and 

 we now perceive that even in the highest and most heterogeneous, 

 where the number of distinct organs is greatest and their respective 

 functions most completely restricted to them, some traces of this 

 primitive community remain. We shall conclude our illustration by 

 quoting the account given by Mr. Carpenter of the development of 

 the same system in the embryo of a vascular plant, in which he in- 

 geniously shows its conformity to the same laws. *' In tracing the 

 gradual evolution of the special absorbent system of the more per- 

 fect plants, we may observe many interesting relations between the 

 progressive stages of its development and the permanent forms of the 

 system in the lower orders. Thus the embryo at its first appearance 

 within the ovule is nothing but a single cell, like that of the Proto- 

 coccus, in the midst of the store of semi-fluid nutriment prepared by 

 its parent, which it gradually absorbs by its whole surface, just as 

 do the simplest cellular plants. At the time of the ripening of the 

 seed we mark the rudiment of the future root, which is developed 

 during germination ; but in the early stages of this process the radi- 

 cle simply prolongs itself into the ground, and appears to be equally 

 capable of imbibing moisture through its whole length, like that of 

 the fungi or mosses. It is not until the true leaves are evolved that 

 the root begins to extend itself by ramification, then first protruding 

 perfect fibrils composed of woody fibre and vessels and terminated 

 by spongioles," 



We need scarcely point out the additional interest which is given to 

 ihe facts of science when they thus become subservient to the esta- 

 blishment of those generalizations in w^hich true science consists. 

 Again, to quote our author's language, '* At every successive step 

 we are led to comprehend new relations between facts that pre- 

 viously seemed confused and insulated ; new objects for what at first 

 seemed destitute of utility ; and in the same proportion will the con- 

 templative spirit be led to appreciate the vastness of that Designing 

 Mind, which, in originally ordaining the laws of the animated world, 

 could produce such harmony and adaptation amongst their innume- 

 rable results." 



Having thus endeavoured to communicate to our readers an idea 

 of the objects and spirit of this treatise, we shall briefly indicate its 

 contents. It is divided into two books, the first of which is devoted 

 to general physiology, the second to special physiology. These, 



