THE DICOTYLEDONES 1805 



may be red or variegated in colour. The species of Acer generally produce 

 good timber and in this country Maple wood is used in the manufacture of 

 furniture and also in turnery. Good charcoal can also be manufactured 

 from the waste timber. 



The Aceraceae are well represented in the Tertiary strata and fossil 

 species appear to have been widely distributed in circumpolar regions 

 during the Oligocene. From this it has been deduced that the family is of 

 Arctic origin and travelled south during Tertiary times till it was more 

 widely distributed than it is today. 



The Hippocastanaceae are a small family closely allied to the Aceraceae, 

 and are important chiefly because they include the genus Aesculus which is 

 distributed in north temperate regions and in South America. The most 

 important is A. hippocastannm, the Horse Chestnut (Fig. 1699), which is the 

 only present-day European species, growing wild in Greece and xA.natolia. 

 In PHocene times it was widely distributed in central Europe. The tree 



Fig. 169Q. — Aesciihis hippocastanum. 

 Horse Chestnut. Inflorescence. 



was introduced into cultivation in 1576 and was first planted in England a 

 century later. At the present time a number of hybrids are in cultivation 

 produced by crossing this species with A. carnea, a North American species. 

 Other American species, A. pavia with red flowers and A. glabra with yellow 

 flowers, are also extensively grown. The seeds are large and are enclosed in 

 a leathery capsule which may be spiny or smooth according to the species. 

 Oil can be expressed from the seeds which was formerly used as a cure for 



