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Leaves, he said, are useful to the botanist as marking the broad 

 difference between the two great divisions of flowering plants, mono- 

 cotyledons and dicotyledons, the one having netted and the other 

 parallel veins in the leaves. Besides this the botanist finds constant 

 pleasant puzzles in the forms of the leaves, as was shown by the 

 leaves of Begonia, which are always lop-sided ; by the leaves of 

 Echeveria, which work on a quasi-hinge, and by the leaves of Bomarea 

 in which the apparent upper side is really the under side, each leaf 

 having a complete twist in the pedicel. The leaf of the Rubus 

 australis was also shown together with the leaf of the Rubus arcticus, 

 the one being the most northern, and the other the most southern 

 Bramble known. In the northern form the leaves were entire and the 

 ribs prominently marked ; in the southern form the leaves were com- 

 pletely attenuated, so that only the raid-rib remains with a very slight 

 leafy termination, and the ribs are reduced to the form of short thorns. 



Leaves are good weather-prophets. In a drought leaves will often 

 remain unaffected for a long time, but on the approach of rain they 

 flag ; showing thait they are as sensitive to tlie pressure of the atmos- 

 phere as the quicksilver in the barometer. 



This same sensitiveness is of help to the practical gardener ; as the 

 leaves give the earliest indication of any sickness in the plant. In 

 some few cases the sickness may be in the leaves themselves, as in the 

 case of the curled leaves of the peach and other trees, which arises 

 from the choking of the breathing pores iu the leaves after cold. 



The ofiicinal and commercial uses of leaves were shortly pointed out 

 in the instances of cabbages, and other domestic vegetables, especially 

 of tea ; also in the manufacture of scents and medicines. 



Lastly attention was drawn to the ornamental uses of foliage to 

 the gardener. This was shown in the cultivation of ferns and 

 variegated plants ; which are growu solely for the beauty of their 

 foliage ; and in the growth of our common fossil trees which, with the 

 one exception of the Horse-chestnut, have no conspicuous beauty in 

 their flowers. Attention was then drawn to the growth of trees for 

 their beauty in autumn, and special reference to the recommendation 

 to grow trees with this one object. Mr. EUacombe pointed out that 

 this would frequently be a failuie, as the beauty of autumnal foliage 

 depended so entirely on the season, and the whole beauty was often at 



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