THE SAPROPHYTIC FUNGI OF EASTERN IOWA. 



59 



fully open; inner peridium sessile, depressed-globose, floccose- 

 reticulated, gray or brown, with an irregular, lacerate or 

 stellate ostiole; capillitium and spores brown; threads hyphal, 

 long, branched, interwoven, thinner than the spores, hyaline; 

 spores globose, distinctly warted, 5-10 ,u in diameter. 



This, our most common species, differs so much in many 

 details from other species that Mr. A. P. Morgan thinks 

 proper to use it as type of a new genus. The peculiarities of 

 the species pertain to internal structure, especially the capilli- 

 tium which is poorly differentiated. It seems to us, however, 

 that the genus Geasier is so naturally and easily limited by 

 the peculiar dehiscence of its peridia, that our convenience is 

 more conserved by maintaining the old genus with the limits 

 set by all mycologists from Micheli to Winter. 



The variation in the size of the spores is remarkable, but 

 there is no doubt of it, even when spores from one plant are 

 compared. The hygroscopicity of the outer peridium is 

 always marked, and is long retained, even after the inner 

 peridium with its spores have entirely blown away. 



VI. NIDULARIEiE. 



Spores developed in definite distinct peridioles or sporangia, 

 few in number formed within the peridium of a larger sporo- 

 carp, which is cylindrical or cup-shaped, and at length opens to 

 set free the sporangia. 



The JVidulariccE constitute a group of highly differentiated 

 fungi, small, terrestrial or lignatile, beautiful, distinguished from 

 all others in that the ordinary glebal chambers of gasteromy- 

 cetous fungi are here specialized and developed to form sec- 

 ondary receptacles or conceptacles for the production and 

 retention of the spores. The sporocarp is at first globose or 

 clavate, but presently takes on a characteristic form almost for 

 each genus; at first closed entirely, it at length opens, some- 

 times irregularly, generally regularly by a definite lid-like 

 structure, the epiphragm. The interior of the sporocarp is at 

 first filled with a gelatinous hyphal mass in which one or 

 more spherical or lenticular bodies, the forming sporangia, lie 

 IV— 1 E 2 



