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antiseptic qualities of a high order. The eucalyptus oils from Austra- 

 lia are from the native mixed forests, and are generally of mixed origin. 

 The oils made in California are all extracted from K globulus, and are 

 consequently standard and reliable in their contents of eucalyptol, 

 containing about GO per cent. 



Eucalyptus trees are said to be great absorbents of air moisture, as 

 they are of soil moisture, and for this reason, coupled with the antisep- 

 tic oils contained, have been extensively planted in malarial districts. 

 While the evidence of good resulting from such planting varies greatly, 

 although it is generally assumed that several of the species have a 

 beneficial effect, the improvement of sanitary conditions claimed due 

 to extensive planting of eucalyptus in the Campagna Roinana was, 

 however, by a commission of investigation instituted by the Italian 

 Government, declared to be largely due to other causes. 



ABILITY TO WITHSTAND COLD. 



Most of the species are very tender, enduring but a few degrees of 

 frost. The most hardy can not resist a lower temperature than 25°, and 

 prolonged cold periods, even though less extreme, are fatal. It will be 

 seen from this that the extreme southern parts of Georgia and the Gulf 

 States and California are the only localities in the United States where 

 the temperature is adapted to the genus, and occasionally, as last winter 

 during the exceptional freeze even in Florida, the trees are killed. 

 They are peculiarly free from insect pests, being protected, doubtless, 

 by the essential oils contained in their foliage. 



The species that stand frost the best, and which are also fast growers 

 and good trees, are the following: 



Eucalyptus viminalis, the manna gum. This is a tall, graceful tree, 

 reaching in damp gorges a height exceeding 300 feet. The timber is 

 not very good, nor is there a large amount of essential oil in the foliage. 

 It is a rapid grower. # The common name is derived from a manna-like 

 exudation from the leaves due to the action of certain Australian 

 cicada*. I have never seen the manna here, nor been able to make it 

 appear by wounding the foliage. This tree, in the high Mojave plateau 

 of southern California, has resisted temperature down to 10° F. It 

 stands the English climate. 



E. cocci f era, a handsome tree closely allied to the E. amygdalina, 

 reported as hardy in England. We have only opened trials with it in 

 California. 



E. urnigera, a handsome tree with dark-green leaves, hardy in 

 Eingland, and commencing its trial here. 



E. gunnii. Very rapid grower; in fact, the fastest grower for the 

 first two years we have ever tried. The first year's growth of an E. 

 gunnii has exceeded 2 feet a month, or 2G feet for the year. The tree does 

 not continue its rapid growth as long as the blue gain does. The blue 

 gum grows in its phenomenal rapidity for about ten years, more or less, 



