452 RESEARCHES ON FUNGI 



while the trama, peridium, and stalk are still fleshy. The old speci- 

 mens, at least in our climate (Iowa), dry up and do not putrefy." 



With the help of the microtome, Conard found that the develop- 

 ment of a fruit-body of Secotium agaricoides, in its earliest stages, 

 is precisely like that of Psalliota campestris and P. arvensis as 

 described by Atkinson, 1 and not at all like that of Phallus and 

 Mutinus. The hymenophore was distinctly seen as a horizontal 

 ring of deeply-staining tissue within the globular fungus body of 

 a sporophore only 3-5 mm. in diameter (Fig. 156, No. 1) ; and in 

 another fungus-body, 9 mm. in diameter, the branched and 

 anastomosing gills were found to run primarily in a radial direc- 

 tion and to be extending from the cap to the columella (Fig. 156, 

 No. 2 2 ). 



The spores are olive-green in the mass, ovoid, 7 p long and 5 p 

 wide, smooth, thick-walled, and possessed of an apical germ-pore. 3 

 This pore is evidently homologous with the germ-pore that one 

 finds in the thick- walled spores of Goprini, Panaeoli, Psalliotae, 

 and other chromosporous Agaricineae. The basidia are tetra- 

 sterigmatic and quadrisporous, and a spore often carries with it 

 a part of the sterigma as an appendage. 4 



"The mature gills," says Conard, 5 "are much branched and 

 folded. The tramal tissue consists of long branching and nearly 

 parallel hyphae, whose ultimate branchlets form the densely 

 crowded basidia. There are no cystidia or other aberrant cells. 

 From a fairly dense web in growing stages, the trama becomes 

 looser toward maturity and finally becomes dry and fragile. From 

 the above account it is clear that the carpophore of Secotium agari- 

 coides presents in its origin and development an exact counterpart 

 of that of Agaricus 6 (Atkinson, 1906, 1914). There is at first a 

 universal veil like that of evolvate agarics (Agaricus, Armillaria, 

 and Stropharia). There is an ill-differentiated partial veil. The 

 origin of the hymenophore agrees precisely with that of all recently 

 reported agarics except Hypholoma (Allen, 1906) and Coprinus 



1 G. F. Atkinson, " The Development of Agaricus campestris,''' Bot. Gaz., 

 vol. xlii, 1906, pp. 215-221 ; also, " The Development of Agaricus arvensis and 

 A. comtulus" Am. Journ. Bot., vol. i, 1914, pp. 3-22. 



2 H. S. Conard, Joe. cit., pp. 95-98. 3 - 4 Ibid., p. 94. 



5 Ibid., pp. 97-98. 6 Agaricus = Psalliota. 



