136 • BOTANT. 



(3.) Root-stochs, wliich are bract or Bcale-bearing, usually 

 weak, and subterranean. 



(4.) Tubers, which are bract or scale-bearing, short and 

 thickened, and subterranean. 



(5.) Corms, which are leaf -bearing, short and thickened, 

 and subterranean. 



(6.) BuTb-axes, which are leaf -bearing, short and conical, 

 and subterranean. 



(7.) Flower-axes, which are bract, perianth, stamen, and 

 pistil-bearing, short, and usually conical and aerial. 



(8.) Tendrils, which are degraded, slender, aerial cau- 

 lomes, nearly destitute of phyllomes. 



(9.) Thorns, which are degraded, thick, conical, aerial 

 caulomes, nearly destitute of phyllomes. 



173. — Phyllome.* The phyllome is always a lateral 

 member upon a caulome. It is usually a flat expansion and 

 extension of some of the tissues of the caulome. Its most 

 common form is (1) the iea/ (foliage), which is usually large, 

 broad, and mainly made up of chlorophyll-bearing paren- 

 chyma. 



The other phyllome forms are : 



(2.) Bracts, which are smaller than leaves, generally green. 



(3.) Scales, which are usually smaller than leaves, wanting 

 in chlorophyll-bearing parenchyma, and with generally a 

 firm texture. 



(4.) Floral envelopes, which are variously modified, but 

 generally wanting in chlorophyll-bearing parenchyma, and 

 with generally a more delicate texture. 



(5.) /S'^awiews, in which a portion of the parenchyma de- 

 velops male reproductive cells (pollen). 



(6.) Carpels, bearing or enclosing female reproductive 

 organs (ovules). 



(7.) Tendrils and Spines, which are reduced or degraded 

 forms, composed of the modified fibro-vascular bundles, and 

 a very little parenchyma ; in the first the structures are weak 

 and pliable, in the latter stout and rigid. 



The altogether special modifications of the phyllome, as in 

 pitchers and cups, will be noticed hereafter. 



* From the Greek ^XXov, leaf. 



