HYMENOGASTRACEAE 25 



SCLEROGASTER Hesse 



Fruiting bodies white, subglobose, small, rooted by several fibrils; peridium soft, 

 flocculent, but persistent, often connecting with byssoid mycelium which runs about 

 conspicuously through the substratum; cavities very minute, round to oblong, becoming 

 nearly completely filled with spores; hymenium disappearing, being replaced by spores; 

 septa very inconspicuous at maturity; spores abundant, spherical, warted, yellow. 



The genus was established by Hesse to contain the plant called Octaviania compacta 

 by Tulasne and up to the present no other species has been added. Our plant is the 

 first record of the genus in America outside of California. 



Tulasne, recognizing the striking distinctness of the species 0. compacta, reluctantly 

 placed it in the genus Octaviania saying, "This species differs much from all the hypog- 

 enous fungi which we have seen, and it is with doubt that we place it in the genus 

 Octaviania. In fact it has none of the sterile base, or large, lacunate, sessile chambers 

 of 0. astcrosperma, differing from it in its compactness and in that its chambers become 

 nearly entirely filled with spores. It should perhaps rather be placed with Hydnan- 

 gium, after H. liospermitm or H. hysterangioides; but it differs from these fungi by its 

 mycelium which is much like that of Hysterangium." 



Sclerogaster minor n. sp. 



Plates 17, 18 and 106 



Fruiting bodes small, about 0.3-1 cm. wide by 0.3-0.7 cm. high, subglobose, often 

 irregularly lobed ; buried 2—4 cm. under cedar humus, often more or less covered with a 

 pure white byssoid mycelium which extends through the humus, covering twigs and 

 cedar berries so that the latter may often be mistaken for the fruiting bodies themselves; 

 usually with several considerably branched, mycelioid fibrils extending out from the 

 base or sides of the plants, often connecting two or more plants. Odor faintly 

 earthy. Peridium pure white on young fresh plants, changing only slightly on drying, 

 0.3-0.45 mm. thick, composed of two layers: an outer, very thin, byssoid layer made up 

 of delicate threads which are in places continuous with the mycelium, and the thick 

 inner layer which in young fresh plants is composed of chains of large bladder-like cells, 

 but which in mature plants appears to be composed of large parenchymatous cells; 

 peridium readily separable from the gleba in areas. Gleba pure white when young 

 and fresh, becoming pale buff and finally deep ochraceous yellow when the spores ripen. 

 Tramal plates, 60-185^ thick composed of septate, branched threads 3-5^ thick, 

 continuous with the peridium, continuous also (when it is present) with a sterile plug- 

 like area which may be basal or lateral, and also with a more or less central columella. 

 The plates become very inconspicuous as the cavities and space occupied by the hy- 

 menial layer become filled with spores. Cavities 37-100 x 74-300/u, varying from nearly 

 spherical to long and narrow, becoming almost or completely filled with spores. Scat- 

 tered throughout the plant are numerous crystals. Hymenium forming a distinct layer 

 lining the cavities, obvious only in young plants while the spores are forming, dis- 

 appearing entirely upon their formation, the space occupied by the hymenium being 

 filled with spores; composed of basidia and long, slightly acuminate cells; basidia long, 

 irregularly cylindrical, 4—7.4 x 28-40/j, bearing 1-5 spores, three being the commonest 

 number, sterigmata quite conspicuous, thick and of equal diameter throughout their 

 length, part or all of the sterigmata remaining on the spore as a distinct stalk which 

 varies in length from a very small fraction of the diameter of the spore to about as long 

 as half the spore's thickness. 



Spores 7.4-9.5;u thick, spherical, at first smooth, becoming covered with conspicu- 

 ous warts upon maturing, often with a pedicel. 



