BY THOS. STtF.L. 491 



examined by me certainly i'ontained nitrogen, though by comparison with some 

 of the other fungi the amount is not high. 



The method used for the nitrogen determinations was the Kjeldahl-Gunning. 



VI. Exudation' ffsom Mtoporum platycakpum R.Br. 



In January, 1921, there was forwarded to Sydney Botanic Gardens a sample 

 of a dark brown sugary-looking mass which had been found by Mr. P. "Webb 

 in a hollow h'unk of the above tree at Barton, S. Australia. This was kmdly 

 handed to me by Mr. Maiden for investigation. Examination showed it to 

 consist of impure mannitol from which the pure substance could be readily 

 obtained by extraction with hot alcohol, the mannitol crystallising out on 

 cooling. 



A similar exudation fiom a tree of the same species was obtained during 

 the Elder Exploring Expedition to Central Australia. This was analysed by 

 Mr. H. G. Smith and the results published by Mr. Maiden (Trans. Royal Socy., 

 S. Aust., xvi., 1892, p. 1). 



For the analysis of the Barton sample 1 am indebted to my colleague Mr. 

 E. F. Vaughan. For purposes of comparison 1 have placed the figures of 

 both analyses together: — 



Elder Expedition. Barton. 



Central Australia. South Australia. 



Maimitol 89.G5 44.0 



Reducing sugar . . 2.87 5.4 



Other sugars 0.51 — 



Gums, insoluble, &c 2.37 40.8 



Ash 1.10 1.9 



Water 3.50 7.9 



100.00 100.0 



The exudation is known to occur from jiunctures made by insects. 



The Barton sample resembled lumps of coarse raw cane sugar and con- 

 tained somewhere about 10 % of insoluble matter, principally vegetable debris. 

 It had evidently undergone some deterioration. Barton is a station on the East- 

 West Railwav Line crossing the Australian desert. 



