NA TORE 
[Marcu 24, 1904 
any sort, but for its revelation of the matchless moun- 
tain and marine scenery of Greece, Sicily, and the 
Adriatic coast, for its breaths of an intoxicating air, 
and for the side-lights it throws on Greek peasant in- 
teriors and a rural life, which few foreigners have seen 
as often, and known as intimately, as our author. He 
shows himself typically American, restless, strenuous, 
adventurous, claiming the 
do everything, within the of a 
physical capacity 
| pods, and trilobites. 
right to go everywhere and | 
man, but at the same time in singular sympathy with 
a land and people so little like his own. The book is 
very pleasant reading for all who know Greece, and 
should serve to excite many, who do not, to visit one 
of the loveliest lands on earth. DIG. He: 
OUR BOOK SHELF. 
Ueber verschiedene Wege phylogenetischer Ent- 
wickelung. By Prof. O. Jaekel, Berlin. Pp. 60; 
28 figures. (Jena: Gustav Fischer, 1902.) Price 
1.50 marks. 
THERE are three dominant ideas in this notable essay, 
each requiring for the exposition it merits more space 
fen our limits admit of. 
(1) Besides the gradual changes with which we are 
all familiar, there have been what Galton called 
“ transilient ’’ transformations (‘* saltatory variations,”’ 
“ sprungweise Umbildungen ”’). By individual vari- 
ation within one generation or within a few gener- 
ations, certain animal organisms have undergone pro- 
found, transformations, comparable to the ‘ muta- 
tions’’ described in plants by WKorschinsky and 
de Vries. This is an important conclusion, the 
evidence for which is paleontological. Prof. Jaekel 
distinguishes what may be called three grades of 
Variation :—(a) the so-called normal range of  vari- 
ation, changes in the proportions and correlations of 
the structural architecture, limited in final result by the 
conditions of inter-crossing; (b) abrupt deviations 
which transcend the limits of structural correlation and 
cannot be harmonised with the organic unity, which 
are therefore called ‘t anomalies’? or pathological 
aberrations from the evolutionary trend of the species; 
(c) transilient deviations or mutations which bring 
about a new system of correlations, what others have 
called *‘a new position of organic equilibrium, 
lead to the origin of a new * form ” 
removed from the original type. 
(2) Prof. Jaelel endeavours to draw a sharper dis- 
tinction than has hitherto been made out between the 
origin of a species and the emergence of a new struc- 
tural *‘form.’’ The origin of a species is a con- 
sequence of some form of reproductive isolation 
(KXreuzungsausgleich)—of a restriction in inter-cross- 
ing, of an alteration in the radius in mutual fertility ; 
but the structural differentiation which leads up to a 
new ‘‘ form’? is a very different, and it may be much 
more important matter. 
(3) The third, and perhaps the most essentially new 
pe iabuton which Jaekel males to the interpretation 
in various degrees 
of structural transform: itions, is that he does not regard | 
these changes arising by the summation of the 
qualities of. adult forms, but as due to inhibitions or 
accelerations of development in the juvenile plastic 
stages. Each individual ontogeny is a re-creation of 
the inherited ‘ Stammform,’’ with a plastic period in 
which new adjustments mz ly arise. 
While we have indicated the three most conspic uous 
ideas in this essay, we have done it secant justice. It 
SMES the views of an expert palzontologist in re- 
gard to the mechanism of evolution, and is full of 
NO. 1795, VOL. 69] 
as 
» and | 
originality and suggestiveness. The illustrations in 
evidence are chiefly drawn from crinoids, brachio- 
We venture to express the hope 
that the author will expand his essay into a book, in 
which he may condescend to be a little less terse. 
jaca 
Ausgewdhlte Methoden der analytischen Chemie. By 
Prof. Dr. A. Classen and H. Cloeren. Pp. xvi+831. 
(Brunswick: Vieweg und Sohn, 1903.) Price 20 
marks. 
Tus is just the kind of book to which an analyst will 
turn with pleasure. It is well bound, well printed, and 
really beautifully illustrated. It contains, moreover, a 
_ good account of recent methods or improvements in 
old ones, with the necessary details and manipulative 
Kunstgriffe which in analysis often means the differ- 
ence between failure and success. 
The subjects which are included in the volume are 
the estimation of the common gases, water analysis, 
which is fully treated, the analysis of hydrogen 
peroxide, ozone, explosives, the common compounds 
of carbon, sulphur, phosphorus, boron and silicon, the 
cyanides, concluding with a chapter on organic 
analysis. 4 
It would seem ungenerous to try to discover 
omissions or to offer criticisms when the authors have 
given so much, and with such evident care and 
thoroughness. But the book has one weak point 
which is common to many books of this class. The 
authors have not submitted all the methods they de- 
scribe to personal revision (indeed, it would be difficult 
to do so without the expenditure of a good deal of 
labour), but there is no doubt that such a critical ex- 
amination, which would help the reader to a choice of 
his method, would greatly add to the value of the 
volume. 
However, the important point for the analyst is that 
he has in his possession the most recent information 
from a variety of sources which has been collected 
and sifted by a discriminating authority on analytical 
matters, 
In looking through the volume it is evident that the 
analytical work of recent years has lain rather in the 
perfecting of existing methods than in the discovery 
This seems only natural; for although 
of new ones. 
new technical processes are constantly coming into 
operation, the number of new reagents does not in- 
crease pari passu, and it follows, therefore, that the 
demands made upon rapidity and accuracy in technical 
analysis have to be met by the skilful adaptation of old 
processes to new needs. 
An interesting illustration of this is Emmerton’s new 
method for estimating phosphorus in iron, described 
in the appendix to this volume. Phosphorus has 
always been precipitated as phosphomolybdic acid, 
and the precipitate either measured or weighed. The 
drying of a precipitate always means a loss of time. 
By the new method the precipitate is not dried, but 
reduced with zinc and sulphuric acid, and the lower 
oxide of molybdenum which is formed is titrated and 
estimated with permanganate. ols G 
O’Gorman’s Motor Pocket Book. By Mervyn 
O’Gorman. Pp. ix+287. (Westminster : Archibald 
Constable and Co., Ltd., 1904.) Price 7s. 6d. net. 
Ir is not surprising to find that at last a ‘‘ motor ’’ 
pocket book has appeared; in fact, it is a wonder such 
a work has not appeared sooner. Engineers have long 
had their ‘‘ Molesworth,” and now the motorist can 
lay claim to his ‘‘ O’Gorman ”’ when in trouble or in 
doubt. 
This interesting and instructive book is alphabetically 
arranged, thus rendering easy the finding of any par- 
