RHIZOMES 



75 



borne near the base of the parent bulb. In some of the lilies 

 the bulbtls form at the top or crown of the parent bulb; in 

 other cases they form on the lower part of the flower stalk, 

 while in still others they are always borne beneath the scale 

 leaves of the parent. Bulbels vary greatly in their size and 

 number in the different species. 



Corm. — A corm is a short, thick and fleshy stem which is 

 solid throughout. A vertical axis fills the center. The corm 

 is covered with a few thin, scaly 

 leaves. Corms are always sub- 

 terranean. In general shape and 

 appearance a corm resembles a 

 bulb. Common examples of 

 corm are the gladiolus, the crocus, 

 the cyclamen, and the Indian 

 turnip. The corms of the differ- 

 ent species often behave quite 

 differently. The corms of the 

 gladiolus and the crocus are 

 reproduced annually upon the top 

 and at the sides of the parent. 

 As a rule a new corm is produced 

 above the old one each year, which 

 commonly bears flowers the follow- 

 ing year. 



Rhizomes. — Rhizomes are sub- 

 terranean stems bearing scale 

 leaves. They grow more or less 

 horizontally and the internodes 

 vary in length and in thickness; 

 they bear roots at the nodes. Every 

 species has a type of rhizome 

 peculiar to itself. Familiar examples of rhizomes are the 

 slender root stocks of the mints and the thick, fleshy ones of the 

 canna and the iris. Rhizomes are easily distinguished from 

 roots by the leaf scales in the axils of which are born buds. 

 In the majority of cases the buds of a rhizome are exceed- 

 ingly tenacious . of life, making the plants bearing them 

 difficult to destroy and the propagation of the plant 



Fig. 25. — Side and top views 

 of a corm. 



