The mallee (_Eucalyptus dumosa_) is one of the strangest products of a strange country. The root is a globular mass, varying in size from a child's head to a huge mass which a man can hardly carry. From this bulb a tap root descends to a great depth to reach moist ground below, while other roots spread more horizontally. Above ground a few saplings shoot out to a maximum height of about twenty feet, each sapling having a tuft of leaves at its top. The appearance is that of a skeleton umbrella, with the central stick or handle removed. No surface water is to be obtained in the mallee district; its silence is only disturbed by the melancholy wail of the dingo. Miserable is the fate of the luckless wretch who wanders into such tracts as these. Unable to discern his way, or to gain any point of vantage, and suffering from thirst, the man's reason often succumbs, and he perishes a maniac. Yet the Victorian mallee district is now being cleared by energetic colonists, who aver that when they have exterminated the rabbit, and poisoned the dingo, and got rid of the scrub--which succumbs to treatment--these plains will prove the most fertile in Australia. Here allusion may be made to the question whether or not the eucalyptus is a fever-destroying tree. The subject has been thoroughly investigated and discussed by Mr. Joseph Bosisto, M.P., Commissioner for Victoria at the Colonial and Indian Exhibition, 1886, and his decision is in favour of the utility of the eucalypt. Mr. Bosisto dwells specially upon the fact that malarious diseases are not native to Australia, and that imported fevers are believed to diminish in virulence; and he directly connects the absence of malarious disease with the presence of a peculiar aroma-diffusing vegetation. Mr. Bosisto mentions the powerful root action of the eucalyptus, which, being an evergreen, is continually at work, absorbing humidity from the earth, and upon its large leaf exudation of oil and acid. His contention is that the volatile oil thrown off by the eucalyptus absorbs atmospheric oxygen, and transforms it into ozone. This much is certain: that if a small quantity of any of the eucalyptus oils be sprinkled in a sick room, the pleasure of breathing an improved air is realised at once. And as Mr. Bosisto contends that he has established the diffusion of volatile oil by the eucalyptus, and the chemical consequences of such diffusion, he submits with a calm confidence that 'there is an active agency in Australian vegetation unknown in other countries,' and that the eucalyptus is rightly described as an anti-fever tree.