ARMILLARIA MELLEA 93 



hymenial surfaces come to look downwards to the earth under 

 normal conditions. The period of spore-discharge continues for 

 at least five days and possibly for a longer time. As already 

 recorded, my observations in this connection were cut short by 

 slugs (p. 85). The pileus-fiesh is thick and firm, and the stipe 

 stout. The fruit-body as a whole is both structurally and func- 

 tionally a relatively persistent one. 



The hymenium is composed of basidia and paraphyses only. 

 Cystidia are lacking on the sides of the gills. The basidia are 

 relatively long, thin, and closely packed. The paraphyses are 

 numerous and, in general, have the same distribution and import- 

 ance as in Panaeolus campanulatus. The hymenial elements arise 

 on branching cells which spring from the trama and constitute 

 the subhymenium. 



The chief point of interest in the hymenium is the distribution 

 of the spore-bearing basidia, for upon this depends, as we have seen, 

 the differentiation of the Armillaria Sub-tj^pe from the other Sub- 

 types of the Aequi-hymeniiferae. This distribution on the first day 

 of spore-discharge is shown in Fig. 39 at A, and for the second day 

 in the same figure at B. The general appearance of the spore- 

 bearing basidia remained about the same for the first five days of 

 the spore-discharge period. An examination of the two drawings, 

 A and B, permits one to perceive the loose arrangement of the 

 hymenium : basidia of about the same age, as regards the develop- 

 ment of their spores, are not crowded together in groups as in 

 Panaeolus, but are scattered so that, as a rule, they are isolated from 

 one another or, occasionally, two are near one another. Basidia 

 with spores in their earliest state of development are isolated 

 from one another in a similar manner, and so on for any series of 

 spore-bearing basidia of about the same age. The reader should 

 compare Fig. 39 with the corresponding figures for the Panaeolus 

 (Vol. II, pp. 257 and 258), the Psathyrella (pp. 14 and 50), and the 

 Bolbitius Sub-types (pp. 69 and 73). The figures for the first two 

 of these Sub-types afford striking contrasts with Fig. 39 ; but that 

 for the Bolbitius Sub-type is somewhat similar. In a Bolbitius, 

 however, we have very large paraphyses united into a definite 

 system instead of thin inconspicuous cells not so united. Moreover, 



