PHY S ARUM 87 



Sporangia gregarious, scattered, ovoid or globose, pale yellowish or 

 fulvous, opening irregularly above, stipitate ; the peridium double, the 

 outer layer more or less calcareous, the inner delicate, almost in- 

 distinguishable, persistent below as a shallow cup; the stipe long, 

 weak, striate, fulvous or yellow; hypothallus distinct, venulose, or 

 more or less continuous; capillitium pallid or white, dense, with here 

 and there below large continuous yellow calcareous nodules; colu- 

 mella none; spore-mass black; spores by transmitted light, dark brown, 

 rough, 13-15 /x. Varies to forms with single (inner) peridium and 

 simple physaroid capillitium. Vid. descriptions cited for P. auri- 

 scalpimn, P. nitens, etc. 



This interesting form is from our western mountains, and suggests 

 at first a diderma; but the capillitium is entirely unlike that of a 

 diderma in color and structure, and plainly belongs here, Plasmo- 

 dium yellow, on fallen leaves and twigs. Our material is from Prof. 

 Bethel, Denver; and Lake Tahoe, Nevada; later from Dr. Weir, 

 Montana. No doubt common at high altitudes hear the snow-line in 

 mountainous regions, probably around the world. 



As indicated above, this was originally entered as of the genus 

 Leocarpus; the taxonomic history of the form may interest readers 

 who note with surprise the presentation in synonymy here developed. 



About thirty-five or forty years ago Dr. Harkness of California 

 sent to Mr. Ellis of New Jersey a slime-mould which the sender re- 

 ferred to Diderma albescens Phillips, {Grev. V., p. 114, 1877). 

 Ellis sent a small bit to the Iowa herbarium without other comment, 

 save that he thought it a physarum. Sometime later Mr. Ellis re- 

 ceived from Father Langlois, a correspondent in Louisiana, specimens 

 he esteemed the same thing. He expressed the opinion that if this 

 were what Phillips had found in California, it should perhaps be 

 called a physarum. The Louisiana material by his courtesy came 

 also to this table. The material was scanty, in poor condition, and 

 all waited further light. To these specimens the writer paid less 

 attention. They were in the hands of his correspondents and the 

 courtesy of the case required their further consideration by Dr. Rex. 



In 1889 Mr. Holway found in Iowa, a physarum of which he sent 

 part to Ellis and the remainder to the writer who, then engaged on 

 the MyxoTTiycetes of East. Iowa, referred his part of this Iowa gath- 



