BOLBITIUS FLAVIDUS 63 



successive generations, in the latter the basidia are polymorphic, 

 crowded laterally so that there is overlapping of the spores, and 

 arranged in a definite series of generations which usually are four in 

 number. 



Bolbitius flavidus. General Description. — The fruit-bodies 

 which were used for my observations were found coming up on wet 

 matted dead grass in a pasture at Birmingham, England (Fig. 30). 

 Horses had been feeding in the pasture from time to time, but an 

 examination of the dead grass seemed to show that the mycelium 

 had vegetated, not upon horse dung, but solely upon the dead grass. 

 The fungus came up in the same pasture for several years in suc- 

 cession, and was observed in the months of June, July, and August. 

 The fruit-bodies resembled in appearance those shown in Plate 689 

 in Cooke's Illustrations of British Fungi. The species there repre- 

 sented, according to Massee,i is Bolbitius flavidus Bolt. I shall 

 therefore use this name for my species. However, I feel some doubt 

 in regard to the identification, for Bolton's original description fits 

 neither Cooke's illustration nor my specimens in regard to stature. 

 Bolton says that the stipe is 2 inches high ; but Cooke's illustration 

 shows them to be from 2| to 3| inches high, while my specimens 

 were mostly about 3 inches to 3J inches high, with an occasional 

 specimen as much as 5 inches high. The following is a general 

 description of the species, made from my own specimens. 



The pileus, before expansion, is at first ovate and then obtusely 

 conical, slightly plicate at the base, about 1-5 cm. high but occa- 

 sionally higher, decidedly yellow especially at the apex, and covered 

 by a continuous, separable, viscid pellicle. On opening out, the 

 pileus becomes campanulate and finally flattened with the disc 

 slightly depressed (Fig. 30, E). During the expansion of the pileus, 

 the gills split radially from above downwards along their median 

 planes, as in Coprinus plicatilis, Psathyrella disseminata, etc., so that 

 the outer part of the pileus becomes striate and sulcate. The 

 expanded pileus is usually from 2-5 to 3-5 cm. in diameter but 

 exceptionally as much as 8 cm., not infrequently torn radially half 

 way to the centre in one or two places, bright yellow at the centre 

 passing into dull chocolate-yellow toward the periphery, and 

 ^ G. Massee, British Fungus-Flora, vol. ii, p. 204. 



