The Science of Plant Growing 



at the tip, and is provided with a lid. This soon opens and allows the 

 ingress of various insects, which ultimately meet the same fate as those 

 entering the other plants referred to. In fig. 41 (4) the stout downward- 

 pointing teeth around the rim of the pitcher are shown. 



Another plant with similar contrivances of modified leaves is the 

 Australian Pitcher Plant (Cepha- 

 lotus follicularis), (fig. 42). 



The Fall of the Leaf. From 

 the earliest development of the leaf 

 in spring, preparations are being 

 made at the base of its stalk, 

 whereby it will be thrown off' in 

 autumn in the case of deciduous 

 trees and shrubs. This is brought 

 about by the development of a 

 layer of cork cells right across the 

 stalk, exclusive of the vascular 

 bundles. During the autumn, but 

 especially in October and Novem- 

 ber, this layer of cork becomes 

 completed by the maturing and 

 dying of the cells, and it needs 

 only a breeze of wind or a night's 

 frost to snap the vascular bundles 

 and bring the leaves down in 

 showers. The leaves of the Ash 

 are still quite green when this 

 happens. This state of maturity 

 in the leaves of the Peach is 

 favoured by giving abundant 

 ventilation both at the top and 

 bottom of the house in the case 

 of planted trees. Those in pots 

 should be stood outside after the 

 fruit is gathered. Pot Vines may 

 be served in the same way. Estab- 

 lished Vines that are tardy in dropping their leaves may be assisted to 

 mature them by an abundant ventilation, with a dry atmosphere, and a 

 gentle heat from the hot-water pipes. It would be unwise to hasten 

 the process unduly by keeping them very dry at the roots. 



[J. F.] 



Fig. 42. Cephalottts follicularia 



