322 J. H. MAIDEN. 



allied botanically. In other words, a man who professes 

 to discriminate between all species of timber attempts 

 the impossible. 



Exudations — In Proc. Linn. Soc, N.S.W., 1890 I proposed 

 examination of the kinos as an aid in the diagnosis of 

 Eucalypts, and I divided them into three groups according 

 to their behaviour in water or alcohol (spirit). 



1. Ruby Group — Consisting of ruby coloured kinos, 

 soluble in water and alcohol in all proportions. Examples 

 are, all Renantherse except microcorys. 



2. Gummy Group — Soluble in water, but insoluble in 

 alcohol owing to the gum they contain. Examples, the 

 Ironbarks. 



3. The Turbid Group — These kinos are soluble in hot 

 water or hot alcohol but deposit sediment on cooling. 

 Examples, most of the Parallelantherse. This section, 

 however, includes heterogeneous substances and brings 

 together species little allied. It is doubtless capable of 

 further elaboration, but only serves to accentuate variation 

 in the genus. 



Some kinos e.g., E. maculata, are characteristic in appear- 

 ance, having an olive-green colour; perhaps also that of 

 E. corymbosa, of an intense, almost vermillion colour. 



An exudation of less importance is that of Manna. A 

 number of species exude saccharine substances from the 

 leaves and, a very few, from the trunk. The list is being 

 added to slowly, but in most cases the mannas are mere 

 scientific curiosities and of little value in a scheme of 

 classification. They include viminalis, Gunnii, punctata, 

 pidverulenta, Stimrtiana. 



Petiole — D. Mc Alpine and J. R. Remfrey, in Trans. Roy. 

 Soc. Vic, 1890, published a paper entitled "The transverse 

 sections of the petioles of Eucalypts as aids in the deter- 

 mination of species." 



