10 Gen. Sub. 
GENERAL SUBJECTS. 
differentiation in all units of protoplasm alike. Variations in the sur- 
rounding influences over an area would effect small contrasts in degree 
and kind of differentiation. As soon as these became decided, natural 
selection came into play. The differentiating action of the medium 
never ceased to be a co-operator in development, as a cause, both direct 
and indirect, of modifications of structure. With sexual reproduction, 
there came into play causes of frequent and marked fortuitous variations. 
The results of the mixtures of constitutional proclivities were mostly 
suppressed, but sometimes increased, by survival of the fittest. Natural 
selection became the predominant factor in relation to fortuitous varia- 
tions of structure, of no account in the converse with the medium, but 
of much account in the struggle with enemies and competitors.” 
Especially with plants and relatively inactive animals, “the survival of 
individuals, which had varied in favourable ways, must all along have 
been the chief cause of the divergence of species and the occasional pro- 
duction of higher ones. Gradually the inheritance of those modifications 
of structure, caused by modifications of function, becomes more and 
more important.” 
Spitzer, H. Beitriige zur Descendenztheorie und zur Methodologie 
der Naturwissonscliaft. Leipzig : Brockhaus, 8vo, 539 pp. 
*Steinacii, Ad. System der orgauischou Entwicklung naturwissen- 
schaf tlicli-kritisch dargestollt. Th. I. Dio Entwicklung dor Pflanzen 
und Thiere. Basel : Schwabe, 8vo, 642 pp. 
*Sturtevant, E. L. Atavism the result of cross-breeding lettuce. 
Am. Ass. for Adv. of Science, xxxv. 
Sutton, J. B. On Atavism : A Critical and Analytical Study. P. Z. S. 
1886, pp. 551-558. 
Atavism defined as development of transmitted characters normally 
latent. “ Neogenetic ” atavism (where abnormal part is not found as 
a germ in the embryo) has no existence. Atavism in relation to pros- 
tate, and secondary sexual characters. Their non-development, though 
latent, in female. 
„ General Pathology. London : Churchill, 8vo, 380 pp., 149 figs. 
Pathology as a factor in evolution. “ Evolution has played as im- 
portant a part in pathology as in biology, and structural peculiarities, 
pathological in their origin, have been transmitted as race-characteristics 
in more than oue group of animals.” The differences iu the classes of 
animals involve liabilities and immunities. In discussing evolution, 
aberrations in structure and function must be included. 
'Wianna de Lima, A. Exposd sommaire des Theories Transformistes 
de Lamarck, Darwin, et Haeckel. Paris : 4/6, duodec. 
*‘Vogt, C. Quelques hdrdsies darwiuistes. Arch. Sci. Nat. 'Geneve, 
xvi, pp. 330-338. 
Wain Wright, S. Scientific Sophisms. Review of Current Theories 
concerning Atoms, Apes, and Men. Now ed. London : 8vo, 
290 pp. 
