NOTICES OF BOOKS. 261, 



in which those hard, dry balls can by any possibility reach the, in 

 most cases, very small and apparently strangely placed stigma. 



Mr. Fitzgerald seems deeply imbued with the apparent discord 

 between production and use. Thus he says, " Ffrtility is in an 

 inverse ratio to the apparent arrangement for its production" ; 

 again, after mentioning Dendrohium Hillii, a specimen of 

 which had 60 pseudobulbs, 190 spikes, and about 40,000 flowers, 

 yet not a single seed was produced, he seems almost horrified at 

 the " fearful waste of vital power in the production of so many 

 barren flowers, and such an infinity of useless seed," from which he 

 draws a corollary dealing with the vast lapse of time necessary in order 

 to generic and specific differentiation. We think his mind would be 

 eased, so far as concerns the application of this special corollary, could 

 he work out a theory we have looked at with some favour, viz., that 

 the Orchids of Australia are in a special condition, inasmuch as energy 

 is now being directed towards vegetative as opposed to sexually repro- 

 ductive existence. This is evinced by the wonderful development of 

 tubers and roots, some of which latter organs we believe may possibly 

 be found to be modified leaves. Thus, if this theory could be esta- 

 blished, it would follow that the presumed waste might prove to be 

 the better of two alternatives, the other being reproduction by 

 ordinary sexual means, the complicated Orchidean apparatus for the 

 performance of which remains in the form of structures uneliminated by 

 natural selection. We also do not see why Orchidology should be set 

 up as aff'ording a special exhibition of the apparent absence of correla- 

 tion between means and ends, for the same utterly mysterious sign is 

 branded by Nature on all her productions. X. 



On Fermentation. By P. Schutzenbeeger. (Vol. XX. of Messrs. 

 King's International Scientific Series.) London, 1876. 



The author of this work has set before himself the task of expounding 

 the various processes to which the term Fermentation is applied, not 

 treating the question simply as a chemist, but also making clear the 

 biological facts which are causes and concomitants of those processes. 

 It was only fitting that in so doing a series of phenomena about 

 which, up to a quite recent period, so much mystery has hung, should 

 be introduced by a historical account of the different views which have 

 from time to time been expressed upon the subject. These views 

 come under three heads. We have, first, the Mechanical theory, upheld 

 by Liebig, according to which fermentation is considered to result 

 from a molecular motion impressed on the fermenting body, this 

 motion being derived from the decomposition of another body in 

 proximity to it ; secondly, those who supported what may be termed the 

 Catalytic theory regarded fermentation as simply the result of successive 

 acts of contact ; the third, most recent, and now universally admitted 

 view, due mainly to the genius and energy of Pasteur, may be termed 

 the Vitalist theory — its formula is : Fermentation as efiect. Vegetation 

 as cause. 



The historical introduction is followed by an account of the dif- 

 ferent alcoholic ferments, species of Saccharomyces, including the 

 recent results of Rees, Engel, &c. into the life-history of these orga- 

 nisms, and an elaborate explanation of the method of obtaining the 



