SECOTIACEAE 



Fruit body above ground and with a short or long stalk which extends as a col- 

 umella entirely through the peridium and is connected with it above; gleba chambered, 

 the tramal plates arising like the gills in an agaric and growing into a gill chamber, 

 anastomosing and crumpling to form numerous irregular cavities which are lined on the 

 inner side by a typical agaricoid hymenium ; tramal plates persisting after the matura- 

 tion of the spores; capillitium absent. Dehiscence ventral around the stem with sub- 

 sequent expansion and in some cases longitudinal cracking, or there may be no true 

 dehiscence (as in RJiopalogaster), the very thin peridium disappearing more or less by 

 collapse. Basidia clavate with distinct apical sterigmata. 



The family as above described is so modified from that of Fischer as to include 

 only the genera Secotium and RJiopalogaster (possibly also Macowanites). We are 

 following Fischer in not considering Elasmomyces as distinct from Secotium. This is 

 about as suggested by Cunningham (1. c, p. 223). A very interesting family with 

 characters suggesting the agarics and apparently connecting them with the Hymeno- 

 gastraceae, which they resemble in later stages of glebal development. Only two 

 genera have been found in the eastern United States. It is interesting to compare 

 here the peculiar genus RJiacophyllus B. & Br. (Trans. Brit. Myc. Soc. 11 : 238. 1926) 

 from the tropics, which externally has the exact appearance of a small, delicate agaric 

 with conic cap. Petch has recently been able to study the plant in all stages. Instead 

 of gills there are borne on the underside of the cap more or less linear groups of bulbils 

 which germinate easily and are the only reproductive bodies. These bulbils arise 

 separately inside a delicate fundamental tissue. They may be at first hollow, soon 

 becoming solid through growth of the palisade-like central tissue. This tissue produces 

 on the inside subspherical cells in rows. It is not stated from what cells of the bulbils 

 hyphal threads originate in germination. 



Key to the Genera 



Peridium tough and persistent Secotium 



Peridium very delicate and disappearing in part at maturity Rhopalogasler 



SECOTIUM Kunze 



Peridium above ground with a long or short stalk, which extends entirely through 

 the sporiferous portion as a stout columella which is continuous above with the pe- 

 ridium. Gleba spongy, cellular; tramal plates arising from the peridium wall and also 

 connected with the top or greater part of the columella and filling the space between 

 them, somewhat lamellate, very sinous with a more or less horizontal direction sug- 

 gesting an unopened agaric with sinuous gills; capillitium not present. Dehiscence 

 basal and longitudinal, the peridium usually separating slightly from the stem below 

 and in some cases expanding more or less, after the manner of a young agaric. Basidia 

 clavate with 2-4 apical, stipitate, smooth or rough spores. 



For a good drawing of the hymenium of 5. krjukmvense, a European species with 

 rough spores, see Bucholtz, 1. c, pi. 3, fig. 4. 



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