Oenothera Nanella. 365 



figure in Fig. 45 on page 236. If the rosette is to become 

 biennial and if tlie conditions of growth are favorable 

 which practically means, if the rosette has plenty of room 

 to grow in, it begins to develop broader and shorter 

 stalked leaves and is recognizable at once, and from any 

 distance, as a dwarf rosette. The leaves are often not 

 much longer than 7-8 cm. at this age whereas the radical 

 leaves of Lamarckiana often attain a length of 30 cm. 

 or more. 



This atavistic stage is, however, more often succeeded 

 by a rosette stage which lasts well on into June but, if 

 the plant is going to be an annual, comes to an end 

 then. During this period the leaves are again very broad 

 and attached to the short stem of the plant by a broad 

 base. Their form is often triangular, the leaves being 

 almost as broad as they are long. If the plants have 

 plenty of room, the outer leaves are pressed close against 

 the ground. The outer leaves at this stage have quite 

 short stalks (Fig. 79 A), the inner ones however are 

 almost sessile, almost ensheathing the others with their 

 broad bases. A full-grown leaf of a rosette of this age, 

 with its petiole is shown in Fig. 52 on page 293 at n. 



But if the plants are growing so thickly that they are 

 cramped for room, their whole appearance becomes quite 

 different but none the less recognizable (Fig. 79 B). The 

 leaves which make their appearance after the "atavistic" 

 stage (v. V.) stand more or less erect, are somewhat nar- 

 rower and have longer petioles but are still set on the stem 

 by a broad base. The result is that the stalks seem to be 

 twisted in a curious way which is not brought out clearly 

 in the figure, but which is so characteristic a feature of 

 the young plant that it is by this character that the young 

 dwarfs are usually first identified ; and they differ from 



