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734- When the vines have reached the tops of the trees 

 or other supports, bamboos may be fixed horizontally from 

 tree to tree or from post to post, and the vines trained along 

 them. The trees must be kept down low, so that the vines 

 do not get out of reach, and the branches must be judicious- 

 ly lopped, in order to prevent too much shade. No animal 

 or artificial manures should be used, but rotten leaves and 

 vegetable soil may be applied to the roots after each crop is 

 gathered. 



735. Fertilisation of tlie flowers. The plants will 

 commence to flower in the second year after planting, 

 and full crops may be expected in the fourth year. In the 

 Sibpur Bota-nical Garden the vanilla creepers are in flower 

 in March and April, and artificial fertilisation is regularly 

 practised, though in the wild state in America fertilisation no 

 doubt takes place through the agency of insects or small 

 birds. The parts of the flower are so arranged that self- 

 pollination is impossible, and therefore it must be effected by 

 some foreign agency. If the flower of the vanilla orchid be 

 examined carefully, the outer floral envelope consisting of 3 

 sepals, and the inner one consisting of 3 petals, may be made 

 out. The lowest of the petals is very different from the 

 others j it is called the lobellum or lip, and it envelopes the 

 column or continuation of the axis of the plant on which are 

 set the curious anther and stigma. This continuation is called 

 the column. At the top of the column is a hood which covers 

 up the anther and pollen masses and below this is the vispid 

 stigmatic surface, protected and hidden by a projecting lip 

 some times called the lamellune. Thus we see that the 

 pollen is shut in by the hood and the stigma is shut in by the 

 lamellune, so that two obstacles prevent self-pollination. 

 The object of artificial fertilisation is to remove these obsta- 

 cles, and to permit the pollen masses to approach the stigma. 

 This is easily effected firstly, by detaching the hood, which 

 is accomplished easily by touching it lightly with a piece of 



