342 
Dr. Pfeiffer, of the Magdeburg gas works, and 
has been revised for the English edition by Dr. 
Harold Colman... It, of course, deals largely with 
German practice, but, as might be anticipated 
from the nature of the industry, the work of Eng- 
lish analysts is here more in evidence than in any 
other section of the book, and all the standard 
methods, both of analysis and photometry, are 
described in ample detail. 
The section on coal-tar is by Dr. Kohler, and 
the English translation has been edited by Prof. 
Green. Although the working up of tar is largely 
a British industry, the greater part of the 
analytical work in connection with it would appear 
to be based on methods devised by Continental 
chemists. 
The section on the organic dyes necessarily 
occupies a considerable portion of the book. It 
is due to Prof. Gnehm, and has been edited for 
the English issue by Dr. Cain. It deals with the 
characters. and modes of valuation of the more 
important raw materials of the colour industry, 
organic and inorganic; of the finished dyes in 
respect to their behaviours on fabrics, mordanted 
and unmordanted, and as regards their fastness 
to light, soap, and various reagents, and closes 
with an account of the more important com- 
mercial dyes, and the general procedure for the 
chemical examination of synthetic and of the 
naturally occurring dye-stuffs. The book is ad- 
mirably printed and suitably illustrated, and is 
furnished with copious indexes, and altogether 
constitutes a worthy addition to the bibliography 
of chemical analysis. 
THE ANCESTRY OF FLOWERING PLANTS. 
Vortrage iiber botanische Stammesgeschichte, 
gehalten an der Reichsuniversitét zu Leiden: 
Ein Lehrbuch der Pflanzensystematik. By J. P. 
Lotsy. Dritter Band. Cormophyta Siphono- 
gamia, erster Teil. Pp. 1055. (Jena: Gustav 
Fischer, 1911.) Price 30 marks. 
IKE the previous volumes of this important 
work, the one (third) recently issued is of 
great value. As a storehouse of information 
gathered from the most varied sources, it arouses 
wonder at the wide field from which it has been 
gleaned; while it is not less marked by the clear- 
ness with which the information is conveyed to 
the reader and the freedom from verbiage, and by 
the stimulating and suggestive discussions of 
general questions and on subjects of special in- 
terest or difficulty. These are dispersed through 
the volume, where they emerge in relation to the 
various subjects; and they witness to the fairness 
‘NATURE. 
UNE 6, 1912 
LJ 9 
are stated, and to the single aim of the author to 
set forth the conclusions that the evidence will 
watrant. 
The present volume is devoted to the Conifere 
and to a part only of the Angiospermia, yet it 
extends to 951 pages of text and illustrations and 
104 pages of index. 
There is much in the volume that is unfamiliar, 
and the conclusions arrived at may at times arouse 
question or opposition rather than command 
assent ; but the statement of each point, and of the 
way by which the conclusion is reached, will in 
every case repay careful consideration. 
Pressure on our space precludes fuller notice 
of not a few matters of great interest, such as 
the division of Coniferee into two groups—Florales 
and Inflorescentiales—assigned to widely difierent 
ancestors; the relationships of Gnetacez; the in- 
dications of primitive structures in flowers of 
Angiosperms, and the difficulties of tracing them 
to gymnospermous ancestors, and of interpreting 
the cells in the embryo-sac. 
Monocotyledons are regarded as derived from 
Dicotyledonous ancestors in two distinct lines, 
(a) the Spadicifloree from a series commencing in 
Anonales and passing through forms like 
Lauracee and Piperales to Aracee (with 
Lemnacez as a degraded type), Palmacez, and 
Pandanacee, and (b) the remaining Monocotyle- 
dons from a series beginning with such Ranales 
as Ranunculacee, and running on through 
Nympheaceee and Ceratophyllacee to aquatic 
families of Monocotyledons (Alismatacez, &c.). 
The more showy families, such as Liliiflore, are 
also derived from Ranales; and from Liliiflore are 
traced the Graminaceze and Cyperacez as types 
extremely modified for wind pollination; while 
Orchidacez and certain allied families are also 
traced to Liliiflore as forms adapted to insects as 
agents in pollination. 
As these two series of Monocotyledons are inter- 
calated among the Dicotyledons, the system of 
arrangement is very unlike those in general use. 
The only remaining series fully dealt with in this 
volume are Aristolochiales, Nepenthales, and 
Rhoeadinez, all as defined by Hallier, and all 
derived separately from Ranales. The first in- 
cludes families so greatly adapted to parasitic life 
that certain of them are extremely degraded in 
structure. The families in Nepenthales agree in 
capturing animals by means of leaves modified to 
form pitchers. In Rhoeadinez are those families 
grouped round Papaveraceze and Crucifere. 
The indications of probable descent are sugges- 
tive and helpful in many cases in the volume under 
review, but of greater value are the excellent sur- 
with which the views expressed by other botanists \ veys of the leading features of interest, structural 
NO. 2223, VOL. 89] 
