Oenothera Elliptica. 393 



able, or even wholly illusory. Perhaps we might even get 

 a constant race of scintillans. 



§ 20. OENOTHERA ELLIPTICA. 



Almost every year there appear amongst my plants 

 isolated individuals with very narrow leaves. There 

 are three types of such. First those in which the narrow- 

 ness is the result of some malformation. Sometimes 

 one half of the leaf in this case is more reduced than the 

 other and the leaf is consequently more or less deformed. 

 Plants of this kind sooner or later return to the normal 

 type of 0. Lamarckiana, and behave afterwards just 

 like this. The narrowness is presumably in this case a 

 pathological phenomenon ; I shall not deal further with it. 



The two other types are constant and maintain the 

 character throughout life. One of the forms has long 

 leaves which are broadest in the middle and gradually 

 taper off to the tip and to the stalk. I call this form 0. 

 elliptica. The other, a much rarer form, has linear, 

 almost grasslike, leaves and will be described in the next 

 section under the name of O. suhlinearis. 



The seedlings of O. elliptica are recognizable at a 

 very early age (Fig. 83 B, to be compared with Figs. 

 64-66, pp. 325-326). Its leaves have long petioles and 

 are very narrow, seldom attaining a breadth of more 

 than 0.5-0.7 cm. for a length of 8-10 centimeters. One 

 result of this is that they assimilate much less carbonic 

 acid than 0. Lamar ckiana, so that they are weak and very 

 easily overgrown by their normal neighbors. But even 

 when they are transplanted early and treated with every 

 possible care they grow very slowly. The plant shown in 

 Fig. 83 B was photographed in July. 



