Oenothera Gigas. 



325 



The cotyledons are at that time still present; but dying 

 off; or perhaps already dead. Figures 63 and 64 repre- 

 sent two plants at this age reduced to the same scale (%). 

 The gigas rosettes are compact, round and stout; the 

 Lamarckianas are looser, their leaves have longer petioles 



Fig. 64. Oenothera Lamarckiana. A young plant in June, 

 a few days before transplanting (V2) ; c, the cotyledon- 

 ary leaves. 



and therefore make less use of the space of ground at 

 their disposal.^ 



Oenothera gigas has only appeared once in my cul- 

 tures — a single specimen in 1895. The event has already 



^ Miss Anne M. Lutz discovered another highly interesting dif- 

 ference between O. Lamarckiana and O. gigas The former has 14 

 chromosomes in its nuclei, like O. biennis and other species, but the 

 nuclei of O. gigas have twice as many, viz., 28. Cf. Science, Vol. 26, 

 Aug. 2, 1907, p. 151., (Note of 1908.) 



