52 ENDOSPOREAE [PHYSARUM 



11. P. tenerum Rex in Proc. Acad. Nat. Sci. Phil., 1890, 

 192. Plasmodium primrose-yellow. Total height 1 to 2 mm. 

 Sporangia glohose, stalked, erect or nodding, gregarious, 

 yellow, seldom grey, 04 mm. diam. ; sporangium-wall 

 membranous with closely-set rounded clusters of included 

 granules. Stalk subulate, slender, opaque, 05 to 1-7 mm. 

 long, pale yellow, and filled with lime above, darker below 

 from the presence of refuse matter. Columella none. 

 Capillitium of very slender hyaline threads forming a regu- 

 larly meshed network, often persistent after the dispersion 

 of the spores, with numerous round or rounded yellow lime- 

 knots, the axils of the branches slender and mostly free from 

 lime. Spores brownish-violet, nearly smooth, 7 to 8/x diam. 

 P. maculatum Macbr. in Bull. Lab. Nat. Hist. Iowa, ii. 

 383 (1893) ; Macbr. N. Am. Slime-Moulds, 47. P. obrusseum 

 Macbr. I.e., 52, in part (1899). Lepidoderma Kurzii Berk, in 

 Herb. ; Mass. Mon., 255 (1892) ? 



PI. 25. — a. sporangia ; b. capillitium and spores ; c. spore ; (Philadelphia). 



This species is closely allied to P. citrinum, differing in the more 

 slender form, in the delicate flexuose capillitium threads connecting 

 the lime-knots, and in the absence of a columella. 



Hab. On dead wood. — Portugal (B.M. 2114); Antigua (B.M. 

 1646) ; Adirondack Mountains, New York (B.M. 1891) ; Ohio (B.M. 

 1213) ; Brazil (B.M. 2115) ; Japan (B.M. 2116) ; Borneo (B.M. 1212). 



12. P. compactum Lister. Plasmodium ? Total height 

 1 to 2 mm. Sporangia stalked, globose or somewhat flattened 

 below, 0-5 mm. diam., erect or nodding, spotted with pure 

 white, grey or bronze colour and iridescent between the 

 rounded spots ; sporangium-wall membranous, with numerous 

 well-defined rounded clusters of closely compacted lime 

 granules. Stalk erect or flexuose, subulate, furrowed, 

 0*5 to 1-5 mm. long, O05 to 0*13 mm. thick at the base ; 

 white and densely charged with lime above, brown or black 

 below from the presence of refuse matter ; or white with 

 chalky section to the base. Columella none, or represented 

 by closely compacted lime-knots forming a globular cluster 

 0-1 mm. diam. near the apex of the stalk, but lying free in the 

 capillitium. Capillitium abundant, of extremely delicate 

 branching and anastomosing threads without expansions at 

 the axils, somewhat persistent, and of a pale bluish colour 

 after the dispersion of the spores ; lime-knots white, few, 

 small, fusiform, except in the central globular cluster. Spores 

 violet-brown, almost smooth, 7 to 9 /x diam. — Tilmadoche 

 compacta Wing, in Proc. Acad. Nat. Sci. Phil., 1889, 48 ; 

 Mass. Mon., 332; Macbr. N. Am. Slime - Moulds, 61. 

 Lepidoderma stellatum Mass. I.e., 252 (1892). Didymium 

 Barteri Mass. I.e., 231. 



