18 THE GASTEROMYCETES OF THE UNITED STATES AND CANADA 



base and from which the tramal plates radiate. Color at first pale greenish, becoming 

 darker and finally about dark Saccardo's olive (Ridgway). Tramal plates with a 

 gelatinous hyaline appearance which persists even in mature plants; quite variable in 

 thickness from one hundred to several hundred microns ; cavities of the gleba labyrinthi- 

 form, long, and narrow, nearly closed with spores when fully mature. 



Spores (of No. 7416) 5-6.2 x 12-15. 5yu, subelliptic, often narrowed toward the 

 distal end, smooth under low power, but appearing minutely punctate under oil im- 

 mersion, with a distinct cup at the mucro end (appearing under ordinary power as two 

 prongs), subsessile on the basidia. Basidia long cylindrical, 5.5-6.6 x 30-42/j, usually 

 with somewhat sinuous walls, bearing two spores, rarely four. 



Odor quite variable: fresh unripe plants with a very faint not unpleasant odor; 

 deliquescing plants when first collected with a very strong odor suggesting that of 

 Clathrus; while deliquescing plants kept covered in the laboratory give off an odor like 

 that of fermenting wine. Taste of fresh plants slightly sweet, not unpleasant. 



It seems that this species, from the literature we have at hand, has been reported 

 only from Europe, North Africa and California. Our plants agree well with the 

 descriptions of both Vittadini and Tulasne. The former author describes his plant 

 as varying from about the size of a pea to a hazel nut, rarely larger, with a closely 

 fitting but separable peridium, from the base of which numerous fibrils extend, 

 some of which run over the surface of the ground. The odor is described as 

 being strongly nauseous, much like that of Clathrus. He reports his plants as 

 being found deeply buried in humus, and occurring in the months of March and 

 April. With the latter author's description and elaborate notes and figures, our plants 

 agree in all essential characters. Tulasne described two varieties which differ from each 

 other in size and in the fact that in one the peridium was much more easily separable 

 from the gleba than in the other. Our plants vary enough in size to include both of his 

 varieties, while in our specimens the separability of the peridium seems to be dependent 

 on the age of the plant, the peridium being separable, but with some difficulty in young 

 specimens, while it often breaks and slips off in collecting mature plants. 



We have examined plants identified by C. Torrend (No. 90) as H. clathroides, and 

 find that his plants agree with ours in practically all characters, the only difference 

 being that the spores of his plants are slightly smaller than in ours. 



Of the six other species of Hysterangium described or recorded by Tulasne, four: 

 E. nephriticum, H. Thwaitesii, H. fragile, and H. stoloniferum, while showing certain 

 points of superficial resemblance, have spores too large for our present plant and show 

 differences in other characters. Of the other two species noted by Tulasne, H. mem- 

 branaceum is admittedly very close to H. clathroides, but differs in having smaller spores 

 according to Hesse's measurements; while B. pompholyx differs in odor and in having 

 spores which are argillaceous in color. The peridium of H. clathroides is described by 

 Hesse as being composed of pseudoparenchymatous cells, a structural character with 

 which our Chapel Hill plant is in agreement, while the peridium of H. pompholyx 

 according to Hesse is without pseudoparenchymatous cells in the peridium. Of the 

 three new species described by Hesse, H. rubricatum differs in being larger, in having a 

 much thicker peridium, and in the clay colored gleba; H. coriaceum differs in having a 

 much thicker reddish peridium and much smaller spores; H. calcareum differs in having 

 the peridium covered with a grayish white, silky flocculence and in slightly smaller 

 spores. 



