6 
YORKSHIRE NATURALISTS* UNION. 
deleterious character to acquire advantages over its competitors, 
which will be transmitted to its descendants. 
The ])robabiIity of the existence of one great evolutionary centre 
From which the chief types of life have arisen was foreshadowed 
many years ago by the late Dr. S. P. Woodward, who thus expressed 
himself: "Specific centres are scattered thickly over the globe, those 
of genera are more thinly distributed, and the points of origin of the 
larger groups become fewer in succession, until we have to estimate 
the probable position of the scene of creation of the primary divisions 
themselves, and are led to speculate whether there may not have 
been some common focus — the centre of centres — from which the 
first and greatest types of life have emanated." 
Fig. 3.— Map illustrating the expulsion from the primary evolutionary area of the earlier 
evolved species or genera and the initiation of discontinuity in their distribution, as exemplified 
in the subdominant molluscan genera Helicella, Helicodonta and Helicigona. 
The paler evolutionary region is indicative of the expulsion of the subdominant genera. 
The accuracy of the location of the chief evolutionary area of the 
world in North Central Europe— or in its vicinity during other 
arrangements of land and water— is further shown by the greatest 
advances of faunal and floral life being restricted to this region, 
which is, and has been, the most active focus of evolutionary change, 
while the fact that this highly endowed area is surrounded on every 
side by life of gradually diminishing dominancy or inferiority con- 
firms its truth, and this ap})lies not only to every other form of 
life, but is equally characteristic and equally true of man himself, 
as North Central Europe is the home of the Teutonic race, the latest 
evolved people and according to Canon Taylor, the great ethnologist, 
is surrounded on almost every side by the various brachycephalic 
iiMtions of ('eltic affinities whom the Teutons have displaced and 
superseded, who as Lithuanians, Slavs, Celts, Umbrians, Latin and 
Doric Greeks. Helvetians, Belgians, Danes, Austrians, Bavarians, etc., 
