Other Characters in Oenothera Lamarckiana. 473 



afford material for statistics of this kind unless we breed 

 them for the purpose. I shall give an account of some 

 isolated observations which will, I hope, incite others to 

 further investigation in this field. 



In Penzig's excellent work on Teratologv (Vol. I, 

 p. 481) the whole genus Oenothera takes up only about 

 half a page. Our O. Lamarckiana is not mentioned there 

 and of course no monstrosities of it are described. The 

 account of the abnormalities of O. biennis, however, is im- 

 portant from our point of view. This plant exhibits an 

 extraordinary tendency to fasciation and often gives rise 

 to pentamerous flowers and 5-9 partite fruits. I can 

 confirm these statements from numerous observations of 

 my own ; I also found the number of stigmas varying in 

 the same way as in Lamarckiana. Clos cites a pistil 

 divided into seven in O. campylocalyx (ibid.), and syn- 

 anthy in Oenothera has been mentioned by Masters (see 

 also Fig. 107). 



Just as in O. biennis, the chief constituents of the 

 monstrosities presented by the Oenotheras growing in 

 the locality near Hilversum and by the families derived 

 from them in my cultures, are fasciations, pentamerous 

 and polymerous flowers, 5-9 partite fruits, and an in- 

 creased number of stigmas. These, together with varie- 

 gation of leaves and tricotyly in seedlings, which occur 

 in other Oenotheras as well, are the common abnormal- 

 ities; the rest, in my experience, are relatively rare. I 

 shall therefore divide the various instances into two 

 groups, the common and the rare ones. 



The rare monstrosities were tolerably well repre- 

 sented in the locality at Hilversum, as compared with 

 other wild plants. This was one of the causes of the 

 lively impression which the great degree of variability 



