THEORY OF EVOLUTION. 
Gen . Sub. 11 
Cunningham, J. T. [See Eimer, G. H. T.] 
Dareste, — . Nouvelles recherches sur le Mode de Formation des Mon- 
stres omphalocephales et sur la Dualite primitive du Cceur dans les 
Embryons de l’embranchement des Vertebres. C.R. cx, pp. 1142-1144. 
Pebierre, Ch. La Theorie de la Monstruosite double. Arch. Phys. 
xxii, pp. 648-657. 
°Dreyer, F. Die Theorie der Biokrystallisation im Allgemeinen uud 
die Skelettbildung der Polycystinen im Besonderen. Jena: 8vo, 
40 pp. 
Eimer, G. II. T. Organic Evolution as the Rosult of the Inheritance of 
Acquired Characters according to the Laws of Organic Growth. 
(Translation by J. T. Cunningham.) London : 8vo, xxviii & 435, 
pp. 4 figs. 
Finn, F. [See Titciiener.] 
Gadow, Hs. Description of the Modifications of certain Organs which 
seem to be Illustrations of the Inheritance of Acquired Characters 
in Mammals and Birds. Zool. Jahrb. v, pp. 629-646, 2 pis. 
The beak of the crossbills, the bill of the wry-billed plover, the tracheal 
labyrinth of the ducks, the tracheal pouch of the emu, the larynx and 
the manubrium sterni of howling monkeys, the stomach of the ostrich, 
the stomach of petrels. 
Geddes, P. On the Origin of Thorny Plants. Rep. Brit. Ass. (1890), 
pp. 870 & 871. 
This problem, discussed as a special instance of the author’s theory of > 
evolution — “ definite or constitutional variations along grooves ol: change,” 
with corresponding limitation of natural selection mainly to its extinctive 
agency. 
Giard, A. . Le principe de Lamarck et l’Heredite des Modifications 
somatiques. Rev. Sci. xlvi, pp. 705-713. 
°Guldberg, G. Om Darwinismen og dens Riekkevidde. Christiania: 
8vo, iv & 128 pp. 
Gulick, J. T. Intensive Segregation, or Divergence through Inde- 
pendent Transformation. J. L. Soc. xxiii, pp. 312-380. 
Segregation, that at first divides the species into sections with reference 
to some one endowment, is always tendiug to intensified segregation, in 
which the sections present differences in regard to an increasing number 
of endowments. Persistent differences are not all adaptational, for some 
have no relation to utility. Adaptational differences are not all advan- 
tageous. But no divergence can bo maintained without the prevention 
of interbreeding. 
. Divergent Evolution and the Darwinian Theory. Am. J. Sci. 
1890, pp. 21-30 ; Aun. N. II. v, pp. 156-166. 
Segregation a necessary condition for the production of divergent 
species and races. The relation of Darwin’s conclusions to this theory. 
