149 



off the resin. Ether dissolves the greater portion of the resin, but 

 instead of the residual resin being dark brown, as in the case when 

 alcohol is used, it is of a golden yellowish colour, and when ignited 

 burns away without residue, while that portion extracted by alcohol 

 after the ethereal extract has been removed, leaves a small quantity of 

 residue. 



The bright yellow resin melts at 83 C. The original resiii 

 extracted by alcohol melts at 110 C., while the alcoholic residue 

 left on removal of the resin soluable in ether does not melt at 140 

 C. It consists partly of inorganic material. As it was present 

 in small quantities, its composition could not be determined in 

 the small portion of material forwarded. The resin obtained from 

 Triodia irritans, R.Br., by ether, in appearance and colour resembles 

 that obtained from Triodia pungens, but it has a lower melting point, 

 melting at 63 C. The brown resin obtained by alcohol, corres- 

 ponding to that obtained by alcohol from Triodia pungens melts at 

 102 C. From the results of the examination of the bodies con- 

 tained in the resinous material of Triodia irritans, it was suggested 

 that the fat found was artificially introduced; its presence would lower 

 the melting point of the resin. Judging from the appearance of the 

 two resins, their colour, odour, melting points, &c., there appears to 

 be but little difference in the resins obtained from Triodia pungens and 

 Triodia irritans, and they may prove to be identical when prepared 

 under similar conditions. 



We have so few records of the finding of the Porcupine resin, that 

 the following is of interest : " Samples of resinous matter from roots 

 of Spinifex, and tunnels made by ants, found here for the first time, 

 lying on the surface of the sandy ground between bunches of Spinifex, 

 apparently made of sand cemented with some agglutinuous secretion 

 of the insect, or what is more probable, the resinous substance 

 found at the roots of the Spinifex plants." (W. T. Tietkens' Explora- 

 tion of West Central Australia, in Trans. Roy. Geog. Soc. Viet., viii., 

 35) . (Report of Horn Expedition to Central Australia, pp. 195 and 

 196). 



Sub-tribe ii. Chloridese. 



72. Cynodon. 74. Eleusine. 



73. Chloris. 75. Leptochloa. 



76. Diplachne. 



72. CYNODON. 



Spikelets one-flowered, awnless, singly sessile in two rows on one 

 side of slender spikes, digitate at the end of the peduncle, the rhachis 

 of the spikelet articulate immediately above the outer glumes, and 

 either not produced beyond the flower or continued into a minute point 

 behind the palea. 



Outer empty glumes two, keeled, persistent or deciduous. 



