turn for an explanation of some unexplained
optical phenomenon, or for particulars of up-to-date apparatus, to
procure a copy of Mr Spitta's book without delay."--_Nature_.

CONVERGENCE IN EVOLUTION. By Arthur Willey, D.Sc. (Lond.); Hon. M.A.
(Cantab.); F.R.S. With Diagrams. Demy 8vo. 7s. 6d. _net_.

This work brings together some scattered facts of parallel development
of outward form and internal structure in the Animal kingdom,
introducing new cases and fresh interpretations. It is, taken as a
whole, an original contribution to the theory of organic evolution,
with special reference to the forms of Animal life.

THE HEREDITY OF ACQUIRED CHARACTERS IN PLANTS. An aspect of the true
Darwinism based on Personal Observations and Experiments. By the Rev.
Prof. George Henslow. With Illustrations. Demy 8vo. 6s. _net_.

A HANDBOOK OF PHYSIOLOGY. By W.D. Halliburton, M.D., F.R.S., Professor
of Physiology, King's College, London. Eleventh Edition, being the
Twenty-fourth of Kirkes'. With nearly Seven Hundred Illustrations,
including some Coloured Plates. Large Crown 8vo. 15s. _net_.

"One of the best manuals for the student which we possess ... the book
is an eminently trustworthy one, and will prove a valuable foundation
for, and introduction to, the large treatises on
physiology."--_Lancet_.

THE BACTERIOLOGY OF MILK. By Harold Swithinbank, of the
Bacteriological Research Laboratory, Durham, and Sir George Newman,
M.D., F.R.S.E., D.P.H., Chief Medical Officer, Board of Education.
With Special Chapters also by Dr Newman on Spread of Disease by Milk
and the Control of the Milk Supply. With numerous Illustrations. Royal
8vo. 25s. _net_.

"Ought to find a place in the library of every medical officer of
health and of every milk-producer. Scientific in method and lucid in
exposition, the authors have given us a really invaluable
text-book."--_Spectator_.

BACTERIOLOGY AND THE PUBLIC HEALTH. By Sir George Newman, M.D., F.R.S.
(Edin.), D.P.H., Chief Medical Officer, Board of Education. With
Illustrations. Medium 8vo. 21s. _net_.

"The present work, though nominally a third edition of 'Bacteria in
Relation to the Economy of Nature, Industrial Processes, and the
Public Health,' is virtually a new book, written with the object of
supplying all that is necessary for the student of hygiene and the
officer of health to know, so far as every-day problems of sanitation
and preventive medicine de