KNOWLEDGE OE THE MUTATING OENOTHEEAS. 



43 



Table IV. — Baces ofO. muricata, Linn. 



Culture. 



0. muincaia, Linn., Winnipeg, Man, 



19 



1> 



Another sowing 



9> 



St. John, N.B 



»1 



99 



?T 



Middleton, N.S, 



99 



>9 



J1 



39 



5) 



39 



9J 



99 



" 0. biennis^ Linn./' Kiel Botanical Garden 



0. murlcata, Linn., Berlin (naturalized) 



>j 



Seal Harbour, Maine 



Number 

 of Plants. 



Another sowing .. . 



Second sowing, , . . 

 Broad-leaved, F. . . 







Bremen Botanical Garden . . . . 



»> 



var. canescens, Robinson, Woods 



Hole, Mass. . . 



11 



2 



10 



4 



8 



5 



33 



21 



17 



37 



148 



186 



» 



H 



>» ^a • • 



69 



29 



Broad- 

 leaved 



4 







3 







5 



2 



33 



21 



16 



11 



Narrow- 

 leaved, 



7 



2 



7 



4 



3 



3 











1 



26 



148 



186 



69 



29 



Eemarts 



^ 



The races from Winnipeg 

 and Middleton are iden- 

 )>tical, and that from St. 

 John is at least ve ry 



closely similar. 







Two plants of the F^ with 

 broad leaves gave only 

 broad in F^. 



Apparently identical with 

 the Winnipeg races. 



f Both races different from 

 \ Bremen culture. 



Uniform race. 



Uniform, same as Berlin 



race. 



Uniform race. 



99 



JJ 





V. (A) CrLTUKES OF Oenotheras prom Lancashire. 



These cultures, wliicli were begun in July, 1907, have developed so many features of 

 interest that a separate account of them is necessary. We may recall that these 

 Oenotheras have been occupying the Lancashire sand-dunes for at least a century, 

 and probably date from a much earlier time. It is, therefore, of much importance to 

 know what has been happening to this complex of forms during the period of its 

 naturalization. An inquiry regarding the process of evolution in such a genus as 

 Oenothera must continually keep in mind a freely-intercrossing population as its 

 starting-point, and as the condition under which its evolution has gone forward. An 

 analysis of the changes which the plants may show as a result of freely commingling for 

 a long period is, therefore, of great importance, especially in its bearing on the relation 

 between crossing and the phenomena of mutation. 



Bailey (1907) first called attention to the fact that O. Lamarchiana was growing on 

 the sand-dunes at St. Anne's-on-Sea, and MacDougal (1907, p. 8) found that seeds from 



g2 



