GUIDE TO THE MODELS OF FUNGI. 



21 



This is frequent among grass in woods and pastures and on 

 downs in autumn. 



37. Agaricus muralis Sow. — Pileus somewhat membranaceous, 



tough, convex, umbilicate, then infundibuliform, radiato-striate, mar- 

 gin crenulate, red-brown ; gills decurrent, distant, pallid ; stalk short, 

 stuffed, smooth, same colour as pileus. 



This grows on old, damp, mossy walls, turf-banks, and turf- 

 walls — hence its specific name. It is more common on the ground 

 among moss and short grass in open places in woods. 



Sub-genus 9. Pleiirotus. — There are more than forty British 

 species oi Pleiirotus, four of which are represented by models. Nearly 

 all grow upon trunks or stumps, a small 

 number on the ground. The stalk, when 

 present, is usually lateral or excentric, but 

 if the plants grow vertically they have fre- 

 quently a central stem. The pilei are 

 usually irregular. Most of the species 

 appear in late autumn or earl}' winter ; 

 Agaricits ostreatiis and A. euosmus are 

 sometimes seen in the spring. 



38. Agaricus ulmarius Bull. — Pileus 

 fleshy, compact, horizontal, regular in form 

 but excentric, convex and smooth, livid- 

 whitish or ochreous-white in colour ; flesh 

 white, tough ; gills sinuate or rounded be- 

 hind, somewhat crowded, whitish ; stalk 

 thick, solid, firm, curved, excentric, white. 



The odour is powerful, and somewhat rank and acid. 



A. ulmarius, although uncommon in some districts, is frequent 

 in the neighbourhood of London, where it grows, singly or gre- 

 gariously, upon old, unhealthy, and damaged trees, hastening their 

 decay. It is usually seen upon the elm, generally high up among 

 the branches. Occasionally it grows upon other trees, as the beech, 

 oak, and poplar. 



It is a " wound-parasite," growing on accidental wounds on 

 trees ; the spores germinate on the wounded surface, and the 

 mycelium penetrates the trunk and causes it to decay. 



It is by some considered esculent, but the flesh is always tough 

 and deficient in flavour. 



Fig. 13. — Type form of Pleurotus. 

 Agaricus corticatus Fr. 

 (One-sixth natural size.) 



39. Agaricus subpalmatus Fr. — Pileus fleshy, convex, then 

 flattened, clothed with a thick, tough gelatinous corrugated pellicle ; 

 gills rounded behind, broad, crowded, paler than pileus ; stalk solid, 

 fibrous, soft, at length hollow, curved, smooth, fibrilloso-striate. 



The imbricated, gelatinous pilei are usually glued together. 



A. subpalmatus is a remarkable and beautiful species, said to be 



