PSATHYRELLA DISSEMINATA 41 



house there was soil and a wooden stage work (B). Although I was 

 unable to investigate the matter in detail, I have little doubt that 

 the ordinary vegetative mycelium of the fungus had been attacking 

 some wood present in the green-house, and that an ozonium had been 

 produced which had penetrated through crevices in the mortar of 

 the joints of the wall and had thus placed itself in an advantageous 

 position for the production of the fruit-bodies. In support of this 

 view, it may be mentioned that on two occasions I have observed 

 the mycelium of Merulius lacrymans, the Dry-Rot Fungus (Fig. 23), 

 passing through a brick wall via minute cracks and spaces in the 

 mortar. In one instance, the mycelium had rotted the wood of a 

 large beam at the top of a cellar wall. From the beam it spread 

 downwards in a fanlike manner over the surface of the whitewashed 

 wall on one side. Then, at a distance of nine inches from the beam, 

 it made its way through the mortar of a horizontal joint, and thus 

 passed to the other side of the wall where its fanlike growth over the 

 bricks was continued. In the second instance, the Dry-Rot Fungus 

 had attacked a wooden cupboard at one end of a very damp cellar, 

 and the woodwork was enveloped with the fleecy mycelium (Fig. 24, 

 A) and a few patches of fruit-bodies. At a distance of about a yard 

 from the cupboard and a yard from the ground, there was a round 

 hole in one of the joints of the mortar. The hole was only about 

 2 mm. in diameter, but through it there passed a mycelial cord to 

 which was attached a mass of fleecy hyphae which spread out on 

 the bricks so as to form a circular patch about six inches in diameter 

 (Fig. 24, B). The builder, who took me to see this cellar, was 

 firmly convinced that the fungus was living at the expense of the 

 bricks and mortar ; but, doubtless, if the wall could have been 

 pulled down, it would have been found that the mycelium from the 

 cupboard had made its way into the centre of the wall and had 

 passed through crevices between the two courses of bricks until the 

 little hole through which it emerged had been reached, the whole 

 of the mycelial growth having been made solely at the expense of 

 the wooden cupboard a yard distant. 



A few remarks may be added here in regard to the position of 

 growth of the fruit-bodies of Coprinus domesticus, which my studies 

 of the genus Coprinus have led me to believe is identical with 



