THURSDAY, AUGUST > 20;)-1914. 
FISHERIES AND FISH-CULTURE. 
Traité Raisonné de la Pisciculture et des Péches. 
By Prof. Louis Roule. Pp. viii+ 734. (Paris: 
J. B. Bailliere et Fils, 1914.) 
RANCE has held aloof from the international 
fishery investigations in which most of the 
other countries of northern Europe have been en- 
gaged during the last decade, and ‘such fishery 
work as has been carried out by Frenchmen has 
progressed upon somewhat independent lines. It 
is therefore interesting to receive a general work 
by a Frenchman dealing with fishes and fishery 
questions in a comprehensive, but at the same 
time somewhat popular way, and to see familiar 
questions looked at from a different aspect and 
treated in a more lively and entertaining manner | 
than that to which we have recently been accus- 
tomed. Although Prof. Roule’s work is a volume 
of more than seven hundred pages, it must, how- 
ever, be regarded neither as a text-book suited to 
the requirements of the student of fishery science, 
nor as a practical handbook for those whose busi- 
ness it is to concern themselves with fishery ad- 
ministration or with fish culture for commercial 
purposes. The general results of much recent 
scientific research are, it is true, explained in a 
clear and illuminating way, but little or nothing 
is said as to the methods, often very laborious 
and involving a close and minute study of a vast 
number of detailed observations, by which those 
results have been obtained. Often, too, we are 
afraid the author does not sufficiently discriminate 
between results which may be regarded as es- 
tablished scientific facts and mere working hypo- 
theses which are useful enough or indeed essential 
as guides to future work, but would not be con- 
sidered, even by those who have fathered them, 
as settled conclusions. Throughout the book there 
are no detailed references to the literature of the 
subject, although there are a number of references 
in footnotes to the names of authors well known 
for their fishery work. 
The book, nevertheless, does fill a very useful 
place of its own. It will appeal strongly to that 
numerous class of fishermen and naturalists, both 
amateur and professional, to whom the habits and 
natural history of fishes, their migrations, their 
modes of feeding and of generation, and the 
general history of their lives are questions of 
never failing interest and speculation. To all 
such it may be confidently recommended. The 
author deals with both sea- and fresh-water fishes, 
and his book is divided into three parts. The first 
part treats in 180 pages of fishes in general and 
NO. 2338, VOL. 93| 
NATURE \ Av@si ioi4 
| 
om tte 
i) 
they live. 
general features of aquatic life are described, and 
the nature of the fixed and floating animals and 
plants found in the sea- and in fresh-water is con- 
of the’ conditteadnalddius: : 
sidered. The structure of fishes and the physio- 
logy of their nutrition, their sensations and their 
reproduction are also treated of in a way that can 
be easily understood and in a logical sequence 
which makes the account both suggestive and 
interesting. Part ii., to which 262 pages are 
devoted, deals with sea fishes and sea fisheries. 
Some account is first given of the physical and 
chemical conditions of sea water, including a dis- 
of tides, and currents. The 
cussion waves, 
' general physical characters of the sea floor are 
also touched upon. This is followed by a more 
detailed discussion of the various methods of 
fishing which are practised both in coastal waters 
and on the high seas. The author has succeeded 
in imparting very great interest into this part of 
his work and, especially when dealing with the 
tunny fisheries, he has introduced an amount of 
vigour and excitement into his descriptions which 
we do not frequently meet with in works of this 
kind. Considerable space is devoted to the 
pelagic migratory fishes, such as the mackerel, 
herring, pilchard, and anchovy, and the many 
different theories as to the extent of their move- 
ments which have been put forward from time to 
time are discussed. The author agrees with those 
modern writers who have concluded that the 
actual distances travelled by the shoals of these 
fishes are by no means so great as was at one 
time supposed. 
Comparatively few pages are given to the ques- 
tion of the hatching and rearing of sea fishes and 
| Prof. Roule is clearly of opinion that no great 
results are likely to be attained by this method of 
attempting to increase the harvest of the open sea. 
His views are summarised in this passage 
(p. 429):—‘‘Mais on connait la faiblesse de la 
pisciculture marine; l’immersion dans la mer de 
plusieurs millions d’alevins n’augmenterait la 
population habituelle que d’une proportion in- 
finitésimale. Les facilités naturelles de la repro- 
duction suffisent d’elles-mémes. Aussi, la méthode 
économique ne consiste point tant a s’ingénier vers 
la piscifacture, comme a favoriser le peuplement 
naturel par la surveillance et la sauvegarde des 
jeunes sur leurs aleviniéres.” 
The third part of the work treats of fresh-water 
fishes and to this subject 255 pages are given. 
This is, perhaps, on the whole, the most satisfac- 
tory part of the book. The author seems to be 
more at home with his subject and to be writing 
more within the limits of his own special experi- 
There can be no question also that practical 
ce 
Ence: 
