86 RESEARCHES ON FUNGI 



by spaces greater than those in the Panaeolus Sub-type or in any 

 other Sub-type whatsoever. The distant separation of basidia bearing 

 spores of about equal age has already been insisted upon above. 



(8) The paraphyses are relatively small and poorly developed. 

 They are not joined laterally into a system of cells so as to form a 

 pavement through which the basidia protrude ; but they are joined 

 into strings of irregular character like those already described for 

 the Panaeolus Sub-type. The paraphyses of the Armillaria Sub- 

 type, therefore, contrast with those of the Psathyrella and the 

 Bolbitius Sub-types as well as with these of all the Coprinus 

 Sub- types. 



From the above it will be noticed that the most striking feature 

 of the organisation of the hymenium of the Armillaria Sub-type is 

 the loose arrangement of the basidia which is of such a nature that 

 spore-bearing basidia of about the same age are distaiitly separated 

 from one another. It is important to grasp this essential character, 

 for, when once grasped, if present in the hymenium of any fungus 

 one is examining in surface view under the low power of the micro- 

 scope, it can be detected at first glance. 



Armillaria mellea. General Remarkg. — Armillaria mellea, the 

 Honey Fungus (Fig. 38, also Vol. II, Fig. 73, p. 203), is one of the 

 best-known of the Agaricineae, for it is commonly found upon and 

 about stumps in both Europe and North America as well as in many 

 other parts of the world. It is characterised by its lignicolous habit, 

 its yellowish-brown squamulose pileus, its somewhat decurrent white 

 gills, and by having a stipe which is yellowish or honey-coloured 

 at the base and floccose up to the spreading rmg. The fungus is 

 conspicuous in the woods in late summer and autumn, because it 

 often occurs in dense tufts or clusters at the base of stumps or dead 

 trees. To mycologists it is particularly interesting because, as 

 Hartig ^ has shown, it is a facultative parasite and as such is some- 

 times responsible for the death of trees. Its mycelium has the 

 remarkable property of exhibiting phosphorescence ; and, when 

 woodmen fell infected trees in damp weather, the chips of wood and 

 bark, as well as portions of the decorticated stumps and trunks, 

 which are left upon the forest floor, not infrequently glow with such 

 1 Robert Hartig, Lehrbuch der Pflanzenkrankheiten, Berlin, 1900, pp. 188-189. 



