110 ME. J. G. OTTO TEPPER ON THE 



Adelaide, the parklands of the city, &c. One finds the dead 

 leaves, grass, &c. frequently quite coated with it ; but I have 

 hitherto failed to notice that this ejected substance is o£ special 

 attraction for the ants, though very numerously present ; and 

 therefore it can scarcely be sweet. I have, besides, found it very 

 abundant in localities where ants were very scarce, and occurring 

 in others where I failed to find a single one. 



When examining a piece of bark fresh from the tree to whicb 

 some of the "melitose" is adhering, one finds the clear fluid 

 always surrounded and frequently overspread, wholly or partially, 

 by a fine white flocculent substance without taste, which, to a 

 considerable extent, prevents flow of the liquid part unless when 

 it augments to an undue degree from several closely adjoining 

 sources. When this takes place, large round drops descend and 

 alight upon the dry leaves, loose bark, grass, &c. scattered thickly 

 under the tree ; and on a cold fresh morning the drops are found 

 in a more or less solid state. 1 have never seen this kind solid 

 during the hot part of the day in any locality examined (Mt. Gam- 

 bier, County Adelaide, Barossa Light, Eergusson), though that 

 does not prove that the melitose of a diff'erent species of insect, 

 and in other parts of Australia, does not solidify by heat. 



On a piece of bark freshly taken from the tree a close exami- 

 nation shows that, the fluffy white substance is thickest in the 

 centre of a ring or oval-shaped deposit of melitose, and forms 

 a complete or partial obstacle to any thing alive that would 

 attempt to enter it. Carefully brushing the flufi" away, a small 

 compressed larva of an insect, evidently of very sluggish habits, 

 is seen ; and this, I have no doubt, is the real producer of the 

 " manna." None occur where the manna is absent ; and the 

 insect is never found without at least an unmistakable trace 

 of the melitose. Of late years both the substance and the insect 

 appear to have become very scarce in such localities as I have 

 examined ; and therefore I have not been able satisfactorily to 

 fix its imago ; but I believe it to be a small greenish Psylla or 

 related genus. 



During 1879 Baron F. von Mueller requested me to turn my 

 attention to the " Lerp " insect which chiefly produces the 

 solid " manna " accumulating around the branches of Eucalypts 

 in white scales. Acting upon his suggestion, I found the spe- 

 cies inhabiting stunted and dwarfed shrubs o^ Eucalyptus oleosa 

 in all its stages. Specimens were forwarded to Baron von 



