THE AMERICAN BOTANIST. 



101 



called. The dominant instinct is seen even in the seedlings 

 which, whether they flower the first season or not, are sure to 

 lay up a store of food in the tap-root which becomes thickened 

 and rounded in the process. If the main stem of such a plant 

 continues to send up new stems for several successive seasons, 

 it is of course, a real perennial, and the species under discus- 

 sion is near to becoming one, but even in the seedling there is 

 manifested a disposition to send out underground stems like 

 the others mentioned and to become not a perennial plant but 

 a perennial succession of plant parts. 



The showy sunflower {H. laetiHoriis) wastes no time in 

 storing food in its roots. It is wholly committed to storing 

 its food where the new plants can use it most readily. Its 

 branches dip down from the base of the stem as in other spe- 

 cies but the food-store is now localized near the tip of the 

 underground part instead of more or less throughout its 

 length. Enlargements of the branch, here and there, however, 

 indicate that the storing of the food in the tips is a character 

 as yet none too firmly fixed. The roots springing from the 

 food-bearing part are now less numerous; in fact, 

 we here have a real tuber though rather longer for 

 the diameter than we are accustomed to fancy such 

 things. It is, howevei so well stocked with inulin, the 

 material allied to starch so commonly stored by 

 Composites, that it is crisp, tender and quite edible. 

 Last in the series comes the artichoke (//. 

 tiiherosus). Its tuber-bearing branches no longer 

 spring from above ground but are given ofif below 



V 



HELIANTHUS LAETIFLORUS 



