62 
NATURE 
[MarcH 19, 1914 
three colour as represented a year or two ago at 
the Royal Institution by M. Gaumont, with such 
amazing fidelity to the colours of Nature. 
Space is not available for more than a bare 
recitation of some of the things described or illus- 
trated; suflicient, however, has been said to show 
that a most interesting and attractive book has 
been produced. 
On p. 171 reference is made to a difficulty met 
with when photographing live microbes in con- 
sequence of their being killed by the heat from 
the concentrated beam from the powerful arc 
lamp. The use of a water cell in the beam is 
described as a method of reducing this trouble. 
While the ever-repeated fallacy of alum solution 
finds no place here, the author or Dr. Comandon, 
whose work is being described, do not appear to 
have known of the use of freshly-prepared solution 
of FeSO,, of such a strength that its colour is just 
visible, as an effective heat absorber. 
C€-VEXBovst 
EARLY FOSSIL BRACHIOPODS.} 
HE work before us, which treats of the 
Cambrian brachiopods of the whole world, 
must arouse the admiration of all who understand 
the difficulties of a comprehensive paleontological 
study of such magnitude. It is a splendid monu- 
ment to the ability and perseverance of its eminent 
author, whose previous reputation as an investi- 
gator ‘of the Cambrian faunas was so widely 
established as not to need the further proof 
afforded by these two handsome volumes. It is 
a matter both for surprise and congratulation that 
Dr. Walcott has found opportunity, amidst his 
many activities, to bring to-completion a task so 
overwhelming : small wonder that it has occupied 
his available time for ten years or more. 
If the wealth and good preservation of the 
Paleozoic Brachiopoda found in North America 
has provided an abundance of material favourable 
for study, how worthily have the paleontologists 
of the United States utilised their advantages ! 
It may be granted that they owe some measure of 
their success to generous practical support and to 
freedom from conservative traditions in the 
matters of outlook and treatment of their sub- 
jects: these are advantages denied to most 
workers in Europe. Yet no consideration of such 
favouring circumstances can diminish our in- 
debtedness to those brilliant investigators in the 
United States who have contributed so largely to 
the rapid advancement of modern paleontology 
in all its branches. For models of comprehensive 
systematic work, for sueeestive and original 
phylogenetic studies, and for inspiring aid in 
applying the facts of paleontology to many 
problems of philosophic biology, we in Europe 
have become more and more accustomed to look 
westward. Dr. Walcott is one among several of 
his compatriots who have advanced our knowledge 
1 **Cambrian Brachiopoda.” By Charles TD. Walcott. Monographs of 
the United States Geological Survey, vol. li.: part i., pp. €72+76 figs. ; 
part ii., pp. 363-+civ plates. (Washington: Government Printing Office, 
1912. 
NO: 231 0"sviOl. 593) 
of the Paleozoic brachiopods in an extraordinary 
degree. 
It is impossible for a single reviewer either to 
criticise in detail a work of such wide scope as 
the present monograph or to do justice to its 
merits. It must therefore suffice to indicate briefly 
some of its special features. In this book are 
described ‘“44 genera, 15 subgenera, 477 species, 
and 59 varieties of Cambrian Brachiopoda,” and 
‘2 genera, 1 subgenus, 42 species, and 1 variety 
of Ordovician. Brachiopoda.” The descriptive 
part of the text occupies nearly 500 pages; yet, 
bearing in mind that this will remain the standard 
work of reference on the Cambrian brachiopods 
of all countries for many years to come, the author 
appears to have erred on the side of brevity. 
There are instances where the specific characters 
might with advantage have been set out more 
fully and the comparative observations amplified, 
though the appearance of an unduly meagre treat- 
ment may sometimes be owing to limitations in 
the material itself. The whole descriptive portion 
of the work affords ample evidence of the author’s 
extensive knowledge and scholarly thoroughness. 
The 76 figures, chiefly in half-tone process, which 
are scattered throughout the text are clearly re- 
produced, while the letterpress is very well printed 
and edited. 
The various tables in which are set forth 
synonymic references and the geographical and 
stratigraphical distribution of the brachiopods, are 
outstanding features of the work. The table of 
synonyms, giving the names now adopted set in 
a column alongside those previously applied to 
the same species, will be of great service to all 
workers in this field of study. Geographical dis- 
tribution is shown in a synoptic table arranged 
according to continents and faunal provinces 
(pp. 114-122). Another elaborate table, giving 
the detailed stratigraphical distribution of the 
Cambrian and some Ordovician species, occupies 
34 pages. This is arranged alphabetically accord- 
ing to states or countries, and contains a vast 
amount of concisely arranged information. Here 
are included summaries of many local or regional 
sections, with references to individual localities 
which are described in detail on subsequent 
pages: also lists of the brachiopods found at the 
various horizons and certain leading species of 
other classes. 
The section of the work headed “ Zoological 
Discussion ” (pp. 291-326) is of importance to all 
students of the Brachiopoda. Here are to be 
found terminological definitions and an account 
of the morphological characters of the shells; also 
short chapters on evolution and classification, 
which strike us as unduly condensed. The biblio- 
graphy (pp. 13-26) is very full, and should prove 
of great help to other workers. We miss here a 
reference to Mr. F. R. GC. Reed’s memoir on “The 
Cambrian Fossils of  Spiti” (Paleontologia 
Indica), published in the summer of 1910, and the 
species of brachiopods there recorded are omitted 
from the descriptive portion of the text. Pre- 
sumably that work appeared too late to be utilised ; 
