102 AUSTRALIAN TREES AND SHRUBS. 



grow too fast for their roots, and are usually blown down by 

 strong winds. A remarkably handsome blue gum at Penmere, 

 near Falmouth, measured by Mr. Elwes in 1911, was 95ft. 

 in height by 7ft. 9in. in girth. It was supposed to have been 

 planted between 1864 and 1867. A tree growing at Torquay 

 measured in 1910 53ft. by 5ft. at twenty years old. There 

 are numerous trees of the blue gum in private gardens in 

 Bournemouth, but none of large size. At Hinton Admiral 

 vicarage the Rev. C. O. S. Hatton reports a young tree seven 

 years old winch is 30ft. high with a girth of 24in. 



At one time the blue gum was regarded as valuable for 

 planting in marshy districts as a preventive of malarial fever. 

 Experiments in this direction were undertaken on the Roman 

 Campagna in the hope that the rapid growth of the blue gum 

 would dry up the marshy lands and destroy by means of the 

 aroma of their leaves all miasmatic emanations. The results 

 proved disappointing, and for the reason recently shown by 

 Ross and Manson, that malaria is produced not by emanations 

 from a marshy soil, but by the presence of an organism in 

 the blood communicated from man to man by mosquitoes. 

 The soundness of this view has been abundantly confirmed 

 by the results obtained in such fever -stricken localities as the 

 Isthmus of Panama and elsewhere. It is admitted that the 

 planting of a fast-growing tree like the blue gum may in- 

 directly have been of benefit by drying up pools in which 

 mosquitoes breed, and by forming a screen which stopped their 

 flight. Beyond this, it is improbable that the blue gum 

 possesses any value not equally shared by other fast-growing 

 trees. Further, the wholesale planting of the blue gum in 

 sub-tropical countries, except in some districts in California, 

 has not been rewarded by the production of serviceable 

 timber. 



E. Gunnii. Tasmania Cider Gum. Also found in Victoria 

 and New South Wales. This was named by its discoverer, 

 Sir Joseph Hooker, in honour of Mr. Gunn. In this species 

 the leaves have scarcely any pungent odour, and on that 

 account it is said that the foliage is liable to be browsed by 



