craterium] physaraceae 93 



above, cartilaginous below, marked with the bases of 

 the calcareous plates of the capillitium. Columella 

 none. Capillitium consisting of an elastic network of flex- 

 uose rigid yellow threads, with numerous free sharp- 

 pointed uncinate branchlets, and of lime-deposits in the form 

 of flat, perforated, pale yellow plates disposed transversely 

 to the axis of the sporangium and connected by broad or 

 narrow attachments to the sporangium-wall, occasionally with 

 irregular lime-knots intermixed. Spores clear violet-brown, 

 minutely spinulose, 9 to 11 fx diam. — Rost. Mon., p. 91 ; Mass. 

 Mon., 337 ; Macbride N. Am. Slime-Moulds, 80 ; Petch in 

 Ann. Perad., iv. 341. Physarwn reticulatum Alb. & Schw. 

 Consp. Fung., 90 (1805) Diderma reticulatum Fr. Syst. Myc, 

 iii. 112 (1829). 



PI. 70. — a. plasmodiocarp (Leicestershire) ; b. portion of a plasmodiocarp with 

 the wall broken and showing vertical plate-like lime-knots ; c. capillitium and spores,; 

 ■d. spore. 



The net-like plasmodiocarps of this species are often very extensive, 

 and may cover an area of several square inches. On maturity the spor- 

 angium wall usually breaks away above, and the capillitium expands 

 longitudinally to many times its original length and lies in orange- 

 coloured festoons about the surface of the wood, leaving exposed the 

 glossy crimson bases of the net-like plasmodiocarps. Mr. Petch found 

 this species to be fairly common at Peradeniya, Ceylon, from April to 

 June in 1905, but he met with no specimen in the four succeeding 

 years. He writes that on exposure to sunlight the rich red-brown 

 colour of the sporangia is soon lost, and they become blackish-brown, 

 while the capillitium is bleached almost white. 



Hab. On dead wood. — Sibbertoft, Leicestershire (K. 1198) ; France 

 (Edinburgh Herb.); Germany (Strassburg Herb.); Portugal (B.M. 

 2846) ; Ceylon (B.M. 2353) ; Java (K. 1772) ; Iowa and Colorado 

 (Herb. Dr. W. C. Sturgis). 



Genus 9.— CRATERIUM Trentepohl in Roth Catal. 

 Bot., i. 224 (1797). Sporangia stalked, either goblet-shaped 

 with a lid of thinner substance, or without a distinct lid 

 and obovoid or sub-globose ; sporangium-wall charged with 

 granules of lime, and cartilaginous at least in the lower part. 

 Capillitium consisting of hyaline threads connecting large 

 lime-knots, some of which often combine in the centre of the 

 sporangium to form more or less of a columella. Stalk 

 cartilaginous. 



KEY TO THE SPECIES OF CRATERIUM. 

 A. Sporangium- wall smooth, glossy; lid distinct : — 



Lime-knots white. 1. C. minutum 



Lime-knots brown. 2. C. continuum 



