CONSTITUENTS 89 



The latex of the Hymenomycetes 1 is of variable composi- 

 tion, and especially of three types, of which the most numerous 

 examples are to be found in the genus Zactarius, which is 

 evidently resinous. There is also the Mycena type, which is 

 confined to a few species of Mycena, and the Fistulina, which 

 is rather more fluid and contains tannin. The latex tubes are 

 large compared with the neighbouring tissue, and much 

 branched, having occasional septa, enclosing a turbid, granular 

 fluid variable in colour. In most species of Zactarius the 

 greatest number of tubes occur in the subhymenial layer and 

 the periphery of the stem ; the former branches in one direc- 

 tion into the hymenium, and in the other into the tissue of the 

 pileus. In Mycena the system is more simple, and the tubes 

 are extremely long, running through the periphery of the stem 

 and ending in the pileus. In Fistulina hepatica the tubes are 

 distributed through the entire receptacle, and are not collected 

 in definite spots, with very few in the hymenium. The milk 

 is persistently white in Zactarius piperatus, vellereus, and many 

 others, sometimes acrid, and in other species quite mild. In 

 Zactarius scrdbiculatus, theiogalus, chrysorrhaeus, etc., it is at 

 first white, then becoming yellow. In Z. deliciosus it is at 

 first deep yellow, and then green. In Z. aspideus and Z. 

 uvidus the milk, which is white at first, becomes lilac. In 

 Zactarius acris the white milk turns reddish, and in Zactarius 

 fuliginosus of a dark yellow, approaching reddish. Not only 

 does the latex differ in colour, in volume, and in taste, but 

 also in consistency. In some it is creamy and sluggish, and 

 in others watery, slightly coloured, and flowing freely. All 

 these features indicate a variability in composition. The 

 character of the yellow juice of Peziza succosa appears to be 

 unknown. 



The phenomenon of phosphorescence has been so long 

 known in Fungi and so often alluded to, that only a brief 

 reference is necessary. Several Agarics have this property of 

 which the largest number, for any locality, have been met with 

 in Australia. All of them are species found growing upon 

 dead wood, and all have white spores. Nearly the same story 

 is related of all of them — to the effect that they emit a light 



1 Journ. Scry. Micr. Soc, vol. vi. (1886), p. 833 ; vol. vii. (1887), p. 627. 



