550 CLASS BASIDIOMYCETEAE 



of the second genus. The tension arising from the osmotic swelling of the 

 cells of one of these layers results in the violent eversion of the inner 

 peridial wall so that the whole glebal mass, 1 to 2 mm. in diameter, is 

 ejected. In Sphaeroholus Miss Walker (1927) has shown that this glebal 

 ball may be shot upward to a distance of over 4 meters. In Nidulariopsis, 

 according to Greis (1935), the distance is short. The basidia in S. stellalus 

 Tode ex Pers. are arranged irregularly in a number of clusters of hyphae 

 intermingled with the basidia, as in Scleroderma, these groups being 

 separated by thin hyphal sheets. In the genus Nidulariopsis there are 

 numerous definite hymenial cavities lined by basidia, as in the Hymeno- 

 gastraceae and Lycoperdaceae. The basidia bear from four to nine spores. 

 The ejected gleba germinates as in Nidulariales by numerous hyphae from 

 all sides. In the course of the rupture of the spore fruit the outer layers of 

 the peridium are split into five or more lobes, in some regards resembling 

 a partially opened Geastrum. 



Order Lycoperdales. The remaining order of the Gasteromyceteae is 

 Order Lycoperdales. This carries on the tendencies noticeable in the 

 Sclerodermataceae of destruction of the glebal tissues to form a dry 

 powdery mass of basidiospores intermingled more or less with sterile 

 hyphae which form the capillitium. The function of the capillitial hyphae 

 in the young spore fruits may well be that of water and food conduction 

 as suggested by Fischer (1936) and Zeller (1939). At maturity these 

 hyphae, now empty and more or less thick-walled, serve to keep the 

 spores loosened up so that they do not escape all at once but gradually, 

 over a longer period. The spore distribution therefore has become entirely 

 dependent upon air currents. The fully grown gleba undergoes autodiges- 

 tion which involves the hyphae of the trama (except those that become 

 the capillitium) and mostly the basidia also. At this stage the contents of 

 the spore fruit form a soggy, water-soaked mass. The water is quickly 

 evaporated or perhaps also returned to the mycelium so that soon the 

 gleba is dry, colored brown to purple, depending upon the color of the 

 spores and of the capillitial threads. 



Fischer (1933) recognized only two families in this order, Lyco- 

 perdaceae and Geastraceae, sometimes united into one family. In spite of 

 the difference in glebal structure in some genera it seems to the author 

 that the Tulostomataceae and Podaxaceae perhaps should find their posi- 

 tion here, as representing in this order the same evolutionary trend toward 

 the stipitate pilear structure as is shown in the series Hydnangiaceae to 

 Secotiaceae in the Hymenogastrales. The knowledge of the early develop- 

 mental stages is lacking in many of the genera but in those that have been 

 studied it seems that the gleba may be lacunar or coralloid in its develop- 

 ment, often the former in the basal, first developed portion of the gleba 

 and the latter in the upper, fertile portion. Whether Podaxis represents a 



