128 
Review. 
The concluding chapter of the First Part of the book is a 
useful “ summary of the working hypothesis,” which contains, of 
course, nothing that has not been dealt with in the earlier chapters. 
Part II. is occupied with a detailed statement of the facts of 
the morphology and development of the sporophyte throughout the 
Archegoniate series. It is really a treatise on this subject, coloured 
to some extent by the author’s strobiloid theory of the origin of the 
sporophyte. It is out of the question in the present review to 
attempt to follow the author through this part of his work, nor is it 
necessary to do so in order to obtain a just idea of his theoretical 
position and the evidence on which it is based. As the reader will 
have gathered from what has been written, the “ Statement of the 
working hypothesis” is so full, and so many facts are cited and 
discussed, that the “ detailed statement ” scarcely lends material 
additional support to the fabric already erected. 
On the other hand of course Part II. provides the student with a 
rich storehouse of facts skilfully set out by a real master of the 
subject. Our knowledge of this branch of botany has increased so 
rapidly of late years and the author has played so large a part in 
building it up, while at the same time he commands such a clear 
and easy style of exposition, that this treatise will necessarily at 
once take its place as by far the best available. If we may single out 
individual chapters which appear specially excellent, they would be 
those on the Ophioglossales—quite a masterly analysis of the facts 
known about this isolated group (though we think there is a good 
deal more to be said than the author would lead us to suppose in 
support of the view that Ophioglossum is reduced rather than 
relatively primitive), and the later chapters on the Ferns, containing 
the author’s most brilliant and convincing work on the sorus and 
sporangium of the Leptosporangiata;. 
With regard to the work as a whole, we are inclined to believe 
that the author would have done better to have made two books on 
the subject, one a comparatively short work setting forth his theory 
of antithetic alternation supported by all available relevant facts, 
a frankly controversial work, but including a very careful and 
detailed examination of the objections to his views ; the other a 
comparative morphology of the Pteridophytic sporophyte, detailed 
and as impartial as might be, with the controversial element reduced 
to a minimum. It might be replied that this is what he has given 
us in Parts I. and II. of the present book, and so in the main it is, 
yet we cannot but think that each would have been better if it had 
been kept separate from the other, and conceived in a distinct 
spirit. Nor can the reader quite avoid the feeling that there is an 
air of the chose jugee about the whole discussion so far as it bears 
on the antithetic theory. 
The title is not altogether fortunate as a description of the 
contents of the work. By far the greater part of the book deals with 
phenomena which have little or nothing to do with the origin of a 
land-flora, except in the sense in which all the phenomena of the 
structure and life histories of vascular plants have to do with it. 
As a matter of fact there is strikingly little discussion of the actual 
origin of land-vegetation. And “ the facts of alternation ” is an 
incomplete description of what is meant. The phenomenon of 
