226 TUMOURS OF EUCALYPTS AND ANGOPHORAS, 



largest of the back country trees), a box, and a mallee. The 

 first-named was the most preferred, as yielding the greatest 

 quantity." The name of the species is not given, but it is said 

 somewhat to resemble "the red gum in appearance — the leaves 

 being narrower and of a silvery colour," and to grow "chiefly on 

 sandy or light loamy soil, and throws out numerous lateral roots 

 at a depth of from six to twelve inches from the surface of the 

 ground." As the Blacks could not get at the v/ater in the water- 

 charged tumours of the Mallees, it is intelligible enough that 

 they preferred to operate on the roots of a water-storing Gum. 

 It is desirable that seedlings of this species should be examined, 

 so that it may be determined whether they are exempt from 

 axillary stem-nodules, or refractory; or, if susceptible, how they 

 are able to get rid of the tumour-shoots. Seedlings of some of 

 the Eucalypts of Central Australia mentioned in iSpencer and 

 Gillen's "Across Australia," also are well worth attention, par- 

 ticularly those of ^. terniinalis and E. eudesmoides, because these, 

 perhaps, may be examples of water-storing Gums, like Bennett's. 



We are not aware that analyses of the root-water of the 

 Mallees have been published. Magarey mentions that, when 

 freshly obtained, the root- water is clear, but that, after standing 

 for some time, it becomes discoloured, and turbid (^.c , p.70). Is 

 the turbidity merely due to a chemical precipitate on exposure 

 to the air, or is it a biological phenomenon ? 



Another matter that is deserving of consideration is, the pos 

 sible significance of the abundance of Lerp-manna on the foliage 

 of some of the Mallees,-at certain. seasons and under certain con- 

 drtions, as. indicating the presence o£ -some form of sugar in the 

 sap, likely to be a source of nutriment to parasitic micrabes. 

 Particulars about its occurrence are given, by Tepper, in the paper 

 already mentioned; and in the Catalogue of tlte Victorian Ex- 

 hibition, 1861, Report on Class iii.,-p.25,. under the head of 

 " Manna." 



PI. xxv., fig. 2, and PI. xxvi., show views of two growing 

 Mallees, with as much soil, as was possible with pocket-knives 

 and hands, scraped away from the base. The first and second 

 of the three probabh' represent E. oleosa. They were taken in 

 the Scrub, 50 miles north of Adelaide, by Mr. A. G. Edquist, to 



