156 FLOWER-GARDENING. 



312. Cuttings are of two sorts: cuttings properly so called, 

 and eyes (319). 



313. A cutting consists of an internodia, or a part of one, 

 with its nodi (59) and leaf-bud. 



314. When the internodia is plunged in the earth, it attracts 

 fluid from thes oil, and nourishes the bud until it can feed 

 itself. 



315. The bud, feeding at first upon the matter in the inter- 

 nodia, gTadually elongates upwards into a branch, and sends 

 organized matter downwards, which becomes roots. 



316. As soon as it has established a communication with 

 the soil, it becomes a new individual, exactly like that from 

 which it was taken. 



317. As it is the action of the leaf-buds that causes growth 

 in a cutting, it follows that no cutting without a leaf-bud will 

 grow. 



318. Unless the cutting has great vitality and power of form- 

 ing adventitous leaf-buds (119), which sometimes happens. 



319. An eye is a leaf-bud without an internodia. 



320. It only differs from a cutting in having no reservoir of 

 food on which to exist, and in emitting its roots immediately 

 from the base of the leaf-bud into the soil. 



321. As cuttings will very often, if not always, develop 

 leaves before any powerful connexion is formed between them 

 and the soil, they are peculiarly liable to suffer from perspira- 

 tion. 



322. Hence the importance of maintaining their atmosphere 

 in a uniform state of humidity, as is effected by putting bell or 

 other glasses over them. 



323. In this case, however, it is necessary that, if air-tight 

 covers are employed, such as bell-glasses, they should be from 

 time to time removed and replaced, for the sake of getting rid 

 of excessive humidity. 



324. Layers differ from cuttings in nothing except that they 

 strike root into the soil while yet adhering to the parent plant. 



325. Whatever is true of cuttings is true of layers, except 



