75 



f 



the plant will gradually undergo rather considerable changes. 

 The next stage will be (Fig. 74) where the leaves have com- 

 menced to come out, and this drawing was made from a plant 

 two months older than the first one described (Fig, 73). We 

 now see that the hypocotyl has been bent and is lying upon 

 the ground. The primary root persists, but has now begun 

 to fade away. Another root-system is formed at this time, 

 consisting of two strong, secondary roots, which proceed from 

 the bases of the cotyledons, which have fallen away. These 

 roots are very long, sparingly branched and rapidly sur- 

 pass the primary one in length and thickness. We there- 

 fore have an umbelliferous plant, where the roots at an early 

 stage are all secondary, while commonly in this order, as it 

 seems according to descriptions, the primary root persists for 

 a long time or even during the whole life of the plant. The 

 rl>izome of the full-grown plant is very short, merely repre- 

 sented by an exceedingly short, vertical axis, upon which 

 ^ buds are at length developed, producing for several years 



* leaves and flowering stems. 



ARALIACE.^. 



A r alia spinas a, 



\ ^ The seeds oi this tree did not germinate for about eighteen 



\ months after they had been sown, and the young plants all 



* showed the peculiar fact, that the cotyledons were unequal 



in size and shape. The one had the common form of a coty- 

 ledon, being oblong and obtuse with the margin entire, while 

 the other one was smaller and ovate, with the margin serrate. 

 That is, however, the only thing which characterized the 

 germinating plantlet of this species (Plate XI, Fig. 75). * The 

 primary root w^as not very strongly developed and showed 

 only two lateral branches, the hypocotyl was rather long and 

 the first leaf next the cotyledons show^ed approximately the 

 Same shape as the final ones, but had only three leaflets* 



URTICACE^. 



Pilea piunila. 



The typical shape of the leaf of this species Is broadly 

 ovate, with a long point and a coarsely serrate margin, a form 



