80, 81.] 



FOKMS OF SCALE-BEAKING STEMS. 



95 



buds called eyes, from which new plants ensue the 

 succeeding year. It is the fact of its origin with the 

 ascending axis, and the production of buds, that places 

 the tuber among stems instead of roots. The Potato 

 and Artichoke are examples. 



238. The stem of the Potato-plant sends out roots from its base, and 

 branches above, like other plants ; but we observe that its branches have two 

 distinct modes of development. Those branches which rise into the air, 

 whether issuing from the above-ground or the under-ground portion of the 

 stem, expand regularly into leaves, etc. ; while those lower branches which 

 continue to grope in the dark, damp ground, cease at length to elongate, 

 swell up at the ends into tubers with developed buds and abundance of nutri- 

 tious matter in reserve for renewed growth the following year. 



265 



63 



\ 



263, Conns of Putty-root (A plectrum) ; a, of last year 6, of the present year. 264, Scale-bulb of White 

 Lily. 265, Scale-bulb of Oxalis violacea. 



.239. THE COKM is an under-ground, solid, fleshy 

 stem, with condensed internodes, never extending, but 

 remaining of a rounded form covered with thin scales. 

 It is distinguished from roots by its leaf-bud, which is 

 either borne at the summit, as in the Crocus, or at the 

 side, as in the Colchicum and Putty-root (Aplectrum). 

 240. THE BULB partakes largely of the nature of 

 the bud. It consists of a short, dilated axis, bearing 

 an oval mass of thick, fleshy scales, closely packed 



