FULIGO] PHYSARACEAE 87 



This conspicuous species has received the popular English name of 

 " Flowers of Tan " from its frequent occurrence in tan-yards on heaps 

 of spent tan. It is perhaps the most abundant and widely distributed 

 of all the Mycetozoa. The colour of the plasmodium is usually bright 

 lemon-yellow, but Dr. Jahn finds in the woods near Berlin a white 

 variety, having the typical small violet spores, maturing from white 

 Plasmodium. The aethalia vary much in size, in colour, and in the 

 amount to which the cortex is developed. It is found that if the rising 

 Plasmodium is protected by a bell-glass from currents of dry air, the 

 sporangia develop well throughout, there is no cortical layer, and a 

 number of small aethalia may be formed rather than a single large one ; 

 when on the other hand the young aethalium is exposed to dry winds or 

 sunlight, the cortex becomes thick. The type of Physarum cerebrinvm 

 Mass., produced in a hot-house at Kew (K. 195), is a form of F. septica 

 with no cortex developed over the convoluted sporangia. In the type 

 specimen of Licea Lindheimeri Berk, from Texas (K. 1648) only the basal 

 part of an aethalium remains ; it is an orange form of the present 

 species with scanty capillitium and violet spores measuring 5 to 7 /x. 



Hob. On dead wood, tan, etc. — Leytonstone, Essex (B.M. 1265) ; 

 Lyme Regis (B.M. 1266) ; Highgate (B.M. 155) ; France (B.M. 459) ; 

 Germany (B.M. 457) ; Austria (B.M. 460) ; Italy (B.M. 461) ; Finland 

 (B.M. 463); South Africa (K. 232); Ceylon (Peradeniya Herb.); 

 Queensland (B.M. 468); New Zealand (B.M. 2331); Japan (B.M. 

 1997) ; Virginia (B.M. 1954) ; Dominica (B.M. 1745) ; Antigua (B.M. 

 1656) ; Brazil (B.M. 2332). 



2. F. muscorum Alb. & Schwein. Consp. Fung., 86, t. vii, 

 fig. 1 (1805). Plasmodium apricot-yellow, translucent. 

 Aethalia pulvinate, 2 mm. to 5 cm. in diam., scattered, clustered 

 or somewhat imbricated, nearly smooth, formed of very closely 

 interwoven sporangia, yellowish-grey or grey, seated on an 

 orange hypothallus ; cortex scanty or none ; sporangium-wall 

 membranous with scattered deposits of orange lime-granules. 

 Capillitium of numerous irregular often branching orange 

 lime-knots connected by rather short hyaline threads. Spores 

 violet-brown, spinulose, 10 to 11 ^ diam. — Macbr., N. Am. 

 Slime-Moulds, 24. Lignidium griseoflavum Link in Mag. Ges. 

 Nat. Fr. Berl, iii. 24 (1809). L. muscicola Fr. Symb. Gast., 10 

 (1817). Reticularia muscorum Fr. Syst. Myc, iii. 91 (1829). 

 Physarum gyrosum Rost. Mon., p. Ill (1875), in part. 

 Licea ochracea Peck in Rep. N. York Mus. Nat. Hist., 

 xxviii. 55 (1879). Fuligo ochracea Peck I.e., xxxi. 56 (1879) ; 

 Mass. Mon., 342 ; Lister Mycetozoa, 67. F. simulans Karst. 

 in Bidr. Kann. Finl. Nat., xxxi. 108 (1879). 



PL 77. — a. aethalium, on moss (Surrey) ; b. capillitium and spores with frag- 

 ment of sporangium-wall ; c. spore. 



This species differs from F. septica in the smooth clustered aethalia, 

 in the orange lime-knots connected by short hyaline threads, and in the 

 larger rougher spores. In some seasons the plasmodium is abundant 

 on turf, rushes, etc., on moist moorland, occurring in masses many 

 inches across, and creeping up the adjacent plants to form on the under 

 surface of their stems and leaves numerous rounded aethalia, whose 



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