76 UNIVERSALITY OF DEGENERATIVE EVOLUTION 



the petiole and the lateral leaflets have atrophied. 



Higher up on the stem 

 (fig. 41, leaves 7 and 8) 

 are some leaves consisting 

 of two stipules and a non- 

 branching tendril. The 

 latter represents the meso- 

 pod and the epipod from 

 which the lateral leaflets 

 have disappeared. Below 

 the foliage leaves, there 

 are usually three leaves 

 which have considerably 

 degenerated (fig. 41, leaves 

 1 to 3). The hypopod 

 is represented by two 

 very small stipules, and 

 the epipod by the tiny 

 point in the centre. The 

 portion of the stem out 

 of which the basilar leaves 

 would grow does not, 

 under normal conditions, 

 emerge from the soil, 

 which accounts for the 

 way in which these leaves 

 have degenerated. 



5. NymphOea dentata. 

 Here the foliage leaves 

 are large, floating, fleshy, 



FIG. 41. Seedling of Lathy ru* 



Aphaca. 

 1, 2, 3, very rudimentary leaves; 4, 5. 



f P ,o7 



terminal leaves turned into tendrils. 



