422 HM, KYLE [DECEMBER 1899 
This includes “those individuals which live within a certain region, 
under equal conditions, have the same habits, and stand in close blood- 
relationship through intercrossing and reproduction.” The characters 
of these individuals will come under the laws formulated here as pro- 
positions II. and III. 
The older systems regarded the above as the species, but in a 
natural system the “species” is the second group. It is a certain 
“combination ” of races whose exact limitation has to be determined in 
all particular cases. The species is but a larger “race,” and may be 
sharply marked off from or merge into the races of another species. 
The sharper the races can be marked off from one another the clearer 
will be the distinction between the species, 
As this paper is so short, it is hardly necessary to make any 
summary. The endeavour has been to display the meaning and im- 
portance of Heincke’s work, and if further information is desired refer- 
ence should be made to the original work. 
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Darwiy, C., ‘‘ Origin of Species,” 6th ed. 1882. 
Duncker, G., ‘‘Die Methode der Variationstatistik,” Arch. Entwickmech. Bd. viii. 
H. 1, 1899. 
Duncoxer, G., “‘ Fr. Heincke, Natur. Geschichte des Herings,” Kritisches Referat Bio/. 
Centralbl. Bd. xix. 1899. 
. Gatton, F., ‘‘ Hereditary Genius,” 1869. 
. GaTon, F., ‘‘ Correlations and their Measurements,”’ Proc. Roy. Soc. 1888. 
Garon, F., ‘‘ Natural Inheritance,” 1889. 
GrppEs, P., and THomson, J. A., ‘‘ Evolution of Sex,” 1892. 
10. Hrincxn, F., ‘‘ Naturgeschichte des Herings,” 1898. 
11. Morean, C. Lu., ‘‘ Animal Life and Intelligence.” 
12. Prarson, K., ‘‘On the Mathematical Theory of Evolution,” 77. Roy. Soc. 1894-95. 
13. PEARSON, K., ‘‘ Chances of Death,” 1897. 
14. Scumipt, H., ‘‘ Anthropologische Methoden,” 1888. 
15. Spencer, E., ‘‘ Principles of Biology,” 1866. 
16. THomson, J. A., ‘‘ Science of Life,’ 1899. 
17. Vernon, H. M., ‘‘ Effect of Environment on the Development of Echinoderm Larve,” 
Trans. Koy. Soc. 1896. 
18. WEISMANN, A., ‘‘The Germplasm,” 1893. 
19. WEISMANN, A., ‘‘ Romanes Lecture,” 1894. 
20. WauaAcer, A. R., ‘‘ Darwinism,” 1889. 
21. Wetpon, W. F. R., ‘‘Certain Correlated Variations in Crangon vulgaris,” Proc. Roy. 
Soc. v. li. 1892. 
22. Werutpon, W. F. R., ‘‘ On Certain Correlated Variations in Carcinus moenas,” ibid. v. 
liv. 1893. 
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OND NO Powne 
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