arcyria] arcyriaceae 239 



rather of Arcyria. A. globosa is distinguished from A. cinerea, its 

 nearest ally, by the globose shape of the sporangia, the less elastic 

 capillitium, and usually by the spiral arrangement of the markings on 

 the threads. An indication of spiral markings sometimes occurs in some 

 of the threads of ^4. cinenea, but less definitely than in the present 

 species and in the reverse direction. Although in North America A. 

 globosa appears frequently on the burs and male catkins of the 

 ' ; Chinquapin " (Castanea sativa Mill. var. americana), it is found 

 there also on dead leaves. Mr. Petch has extended our knowledge 

 of its range by discovering a group of about a dozen typical sporangia 

 on a dead leaf at Peradeniya, Ceylon. 



Hah. On dead leaves, and the burs and male flowers of Castanea 

 sativa var. americana. — New York (B.M. 3052) ; Ohio (K. 882) ; Phila- 

 delphia (B.M. 1871) ; West Virginia (B.M. 1802) ; Ceylon (B.M. 3053). 



6. A. annulifera Torrend Fl. Myx., 102 (1909). Plasmo- 

 dium ? Sporangia scattered, stalked, subglobose or ovoid, 

 0-5 to 0-6 mm. diam., huffish-yellow ; cup of sporangium- 

 wall membranous, papillose, buff, rather deep, with an irregular 

 margin, plicate below. Stalk buff, 0-2 to 0-4 mm. high, rilled 

 with spore-like cells. Capillitium a somewhat flaccid network 

 of slender yellowish threads, 1 to 1-5 ^ diam. , marked at intervals 

 of 1 to 2 fi with prominent ring-shaped thickenings 1 /xdiam., 

 basal threads 2 //, diam., marked with a series of moniliform 

 swellings 2 to 3 /jl long. Spores pale yellow, nearly smooth 

 or marked with a few scattered warts. 6 to 7 fx diam. — Torrend 

 in Bull. Soc. Port. Sci. Nat., ii. 73 (1908) {nomen). 



PI. 185. — c. sporangia ; d. spores and capillitium with fragment of sporangium- 

 wall ; (Portugal). 



This species closely resembles A. pomiformis, but is distinguished 

 by the more slender capillitium being marked with complete annular 

 thickenings. The only example hitherto obtained is the type gathered 

 by Dr. C. Torrend, near Cintra, in the spring of 1908. 



Hob. On pine needles. — Portugal (B.M. 3054). 



7. A. denudata Sheldon in Minn. Bot. Studies, i. 470 

 (1895). Plasmodium white. Total height 2 to 3 mm. 

 Sporangia stalked, crowded or gregarious, ovoid or sub- 

 cylindrical, 0*9 to 1-8 mm. high, 0*8 to 1 mm. broad, crimson, 

 weathering to reddish-brown or brown, rarely pale red ; cup of 

 sporangium-wall membranous, firm, shining, plaited, smooth or 

 marked with scattered papillae and faint broken reticulations 

 on the inner side. Stalk cylindrical, 0-5 to 1 mm. high, 0*1 

 mm. thick, furrowed, red-brown, filled with spore-like cells. 

 Capillitium a rather close elastic network of flattened or terete 

 pale red threads, 2 to 5 jj. diam.. with thickenings in the form 

 of prominent cogs or spines and half-rings arranged in 

 a loose spiral ; with many attachments to the cup, and 

 usually without free ends. Spores pale red, nearly smooth, 

 but marked with a few scattered warts, 6 to 8 //. diam. — 

 Macbr. X. Am. Slime-Moulds, 195. Clathrus denudatus L. 



