AvuGUST 13, 1914] 
NATURE 
607 
a course such as is given in the book now under 
notice we should find them teaching in theit turn 
something rather different from what so fre- 
quently, with us, masquerades under the name 
“nature study.” 
The opening chapters of the book are of a 
general nature. A useful inventory of laboratory 
requirements is followed by practical directions 
regarding the use of the microscope. Methods of 
observation of the living animal are described, 
and thereafter the technique of fixing, staining, 
section-cutting, and so on. A chapter on general 
histology gives good practical directions for ob- 
taining the various types of tissue, and that is 
followed by a chapter on physiology, with good 
practical exercises dealing with digestion, respira- 
tion, milk, blood, and urine. 
About four-fifths of the book are taken up by 
special exercises upon representatives of the vari- 
ous main groups of the animal kingdom. In the 
chapter on protozoa the sporozoa as exemplified 
by Gregarina and Monocystis are taken first, then 
flagellates and while our old _ friend 
Ameceba comes last. This is a reversal of the 
usual order, and its advantage seems to us very 
questionable, for, whatever unexpected complexi- 
ties may turn up in the life-history of Amoeba 
proteus, the fact remains that the ordinary phase 
in the life-history, which alone is studied in prac- 
tical classes represents an extra. 
ordinarily simple and unspecialised type of animal 
—quite without a rival as a subject of study for 
the beginner in zoological science. 
The chapter on Ccelenterata deals with a couple 
of sponges, Leucandra and Spongilla (why not a 
simple Ascon?), Hydra (we notice its coelenteron 
is miscalled ceelom!), Obelia geniculata (the 
figure of the hydroid phase appears to represent 
ciliates, 
in zoology, 
another species), Aurelia, Nausithoe, Actinia, 
Alcyonium, and Corallium. Chapters on worms, 
arthropods, molluscs, echinoderms, tunicates— 
each deal with varicus representative members 
of the group; while vertebrates are illustrated by 
Amphioxus, Petromyzon, Scyllium, 
Rana, Lacerta, Columba, Lepus. 
It will be seen that the book covers a very wide 
area and on the whole it does it well, although 
necessarily some of the descriptions are very 
short. Both in the introductory chapters and 
scattered throughout the book are to be found 
hints on technique valuable even to those who 
have considerable experience. The book is amply 
illustrated, though the illustrations vary much in 
quality. Some are excellent, for example, those 
of Astacus and Hirudo (the latter after Hatschek 
and Cori’s beautiful figures); while others, such 
as that of the transverse section through the 
Nee 2437, VOL. 9a 
Leuciscus, 
earthworm, are very rough. The figures of 
Ascaris eggs should also be revised for a future 
edition. On the whole we find the book wonder- 
fully free from gross errors, and we think it will 
be very useful to students. 
(2) Thus: boolz, 
literary style, 
with its quaint expressive 
and its occasional flashes of 
humour, forms a very readable section of the 
Enzyklopadie der klinischen Medizin. The first 
half of the book is devoted to emphasising the 
importance of the individual constitution as a 
factor in disease. The two extreme schools of 
thought on this subject are referred to: on 
one hand, the extreme bacteriologists to whom the 
body is little more than a test-tube containing 
nutritive medium in which the inoculated microbe 
can grow and multiply, and to whom the mere 
mention of the word constitution is looked upon 
as an attack upon their science; and on the 
other, the extreme constitutionalists, some of 
have gone the length of looking upon 
as the mere harmless accompaniments of 
whom 
germs 
illness. 
The second half of the book is devoted to 
heredity in relation to pathology. Chapter iii. 
gives a crisply written and, on the whole, fair- 
minded summary of the theory of heredity and 
of the main facts of cytology related to it The 
author’s attitude is eminently common-sensible, 
and shows a width of view difficult of attainment 
by the specialist in the study of heredity. He 
gives full credit of the enunciation of the main 
idea of the continuity of the germ plasm to Galton 
in 1875, i.e. before both Jager and Weismann. 
Due space is given to Mendelism. We notice the 
verb “mendeln,” and the substantive ‘“* Nichtsals- 
mendelianer,” though we miss the suggestion of 
still further developments of the vocabulary on 
the lines of mendelacious, mendelacity, men- 
delinquency, mendelette, and so on. The final 
chapter, which might with advantage have been 
longer, gives a summary of some of the more 
important facts of observation in pathology and 
teratology in relation to heredity. 
(3) The author of that admirable encyclopedia 
entitled the ‘Lehrbuch der mikroskopischen 
Anatomie,” has in the work now under review 
succeeded in writing an uncommonly dull book 
upon an uncommonly fascinating subject. The 
way in which the book opens—with the sentence 
“Das volkommenste Forschungs- und Unter- 
richtsmittel, tuber welches die beschreibende 
Embryologie heute verfiigt, besteht darin, dass 
ein Embryo in eine Reihe von diinnen Schnitten 
zerlegt wird, welche mikroskopisch untersucht 
werden kénnen”’—illustrates admirably the cha- 
of the work, which is typically 
racter whole 
