292 Cambridge Manuals of Science and Literature. 
Mr. E. A. Newell Arber in The Natural History of Coal (pp. 
X + 163) gives what seems an excellent summary account of his 
subject. The bulk of the book is naturally devoted to the vexed 
question of origin, and the author concludes that the rival theories 
are by no means necessarily mutually exclusive. “ If we admit that 
some coals have originated under terrestrial conditions like modern 
Peats, while others have been formed in estuarine and lacustrine 
environments, it is hardly possible, in view of the processes of nature 
which may be studied in progress to-day, to deny that in some cases 
coals have been formed in situ, while in others the mother substance 
was transported from a distance to the present site of the seam. 
There is also very little doubt that some coals have been formed 
partly from drifted material and partly from vegetation which grew 
in place. Further, in some cases at least, the products which result 
may be similar, though in one case the mode of accumulation of the 
mother-substance may have been terrestrial, and in another 
estuarine.” (pp. 148-149). 
In Plant-Life on Land : considered in some of its biological aspects 
(pp. 172), Professor F. O. Bower strings together a series of loosely 
connected chapters on various topics which come without any 
difficulty under his very comprehensive title. The first chapter— 
“Present-Day Botany—a Contrast” is interesting as containing the 
first published discussion of the popular misconception of the occu¬ 
pations and range of knowledge of most modern botanists that the 
reviewer has met with. “ Which of us has not been assumed to 
know at once by sight and to be able to name the various Conifers 
growing in the plantations round some country house... The assump¬ 
tion is complimentary, but it is apt to be embarrassing... When one 
is found at fault in the specific distinctions of Abies or Cupressus, 
there is some risk of attainments in other branches being unduly 
discounted. Such knowledge is doubtless desirable, as is all know¬ 
ledge : but to the majority it would be so much mental ballast . . .” 
And the author goes on to give some very wise and judicious 
remarks on the relation of modern specialism to general scientific 
culture. This is one of the most “ readable ” of the recently pub¬ 
lished shilling books on botany, and strikes one as better adapted 
than some of them to appeal to the plain man. 
Professor Seward in Links with the Past in the Plant World 
(pp. X + 142) writes attractively of the Longevity of Trees, of the 
Origin of the British Flora, and then of the Geological Record and 
of typical existing examples of ancient stocks which connect with 
the great dominant groups of plants of the remote past. 
A. G. T. 
K. Madley, Printer, 151 , Whitfield Street, W, 
