The Myxomycetes of the Miami Valley, Ohio. 



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the wall of the sporangium and extending to the columella ; 

 the second, of very slender threads, scarcely branched, and 

 nearly destitute of lime, stretching between the wall and the 

 columella. Spores globose, violaceous. 



A genus founded upon the one remarkable species, and 

 more distinct than any other from the typical genus of the 

 rhysaraceae. In fact, the structure of the sporangium is 

 unique among the Myxomycetes. 



i. PhysareIvLA oblonga B. & C. Sporangium oblong, 

 the apex re-entrant and confluent with the summit of the 

 columella, the base obtuse or slightly umbilicate, stipitate, 

 cernuous. The wall of the sporangium a firm, yellowish 

 membrane, covered with minute granules and with scattered, 

 small, yellow scales of lime ; after maturity the apex is torn 

 away more or less irregularly from the summit of the colu- 

 mella and the wall splits into a few segments, which become 

 reflexed and are subpersistent about the base of the sporan- 

 gium. Stipe long, erect or flexuous, the apex bent or curved, 

 red-brown, rising from a small hypothallus, entering the 

 sporangium and prolonged to the apex as a hollow tubaeform 

 columella. Capillitium of thick, spiniform tubules filled 

 with lime and slender, violet threads, extending between the 

 wall and the columella. The tubules elongated, terete, taper- 

 ing gradually from wall to columella, containing yellow gran- 

 ules of lime ; the threads very slender, outwardly branched 

 a time or two, the further extremities connected by short, 

 lateral branches, often furnished with minute, free branchlets, 

 and containing a few small, fusiform nodules of lime. Spores 

 globose, nearly smooth, violaceous, 7-9 mic. in diameter. 



Growing on old wood, bark, leaves, etc. Sporangium com- 

 monly .8-1.0 mm. in length by .5-6 mm. in diameter, the 

 stipe 1-2 mm. long; the spiniform tubules measure 150-200 

 x 15-20 mic. 



The abnormal forms of this species which sometimes mani- 

 fest themselves are very singular ; the sporangium has a ten- 

 dency to dilate, becoming funnel-form or even salver-shaped, 

 the stipe shortening and even disappearing. I have a large 

 specimen which superficially resembles some lichen, a 

 Pkyscia, for example ; the sporangia are pressed down, flat- 

 tened out, extremely irregular, and in many places confluent ; 



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