physarum] physaraceae 59 



flattened beneath, stalked, nodding, 0-4 to 0-5 mm. diam., 

 yellow, or grey with a yellow base, or iridescent from the 

 absence of lime, smooth ; sporangium-wall membranous, 

 colourless above, yellowish below. Stalk slender, subulate, 

 striate, without deposits of lime, red or copper- coloured. 

 Columella none. Capillitium a close network of slender hyaline 

 threads with numerous yellow flat expansions at the axils ; 

 often persistent and retaining the form of the sporangium 

 after the dispersion of the spores ; lime-knots usually small, 

 angular, yellow. Spores pale violet-brown, almost smooth, 

 7 to 9 fx diam. — Macbr. N. Am. Slime-Moulds, 53. P. cupripes 

 Berk. & Rav. in Grev., ii. 65 (1873) ; Mass. Mon., 284. P. 

 Berkeleyi Rost. Mon., p. 105 (1875) ; Lister Mycetozoa, 47. 

 Didymium flavicomum Mass. I.e., 242 (1892). 



PI. 32. — a. sporangia (South Carolina) ; b. capillitium and spores. 



The red-brown stalks usually free from all refuse matter, the denser 

 net of the capillitium and more angular lime-knots distinguish this 

 species from P. viride. It appears to be closely allied to both P. 

 galbeum Wing., and P. Maydis (Morg. ) Torrend ; from the former it 

 differs in having red-brown, not yellow stalks, and in the well-defined 

 lime-knots ; from the latter in the more slender habit, and in the 

 persistent dense network of the capillitium. 



Hab. On dead wood.— South Carolina (B.M. 439, 870, 993) ; New 

 Jersey (B.M. 1794); New Zealand (B.M. 2139). 



22. P galbeum Wing, in Macbr. N. Am. Slime-Moulds, 

 53 (1899). Plasmodium ? Sporangia globose, scattered, 

 stalked, usually erect, 0-4 to 0-5 mm. diam., bright yellow, 

 smooth ; sporangium- wall membranous, with rather dense 

 clusters of yellow lime-granules. Stalk subulate or nearly 

 cylindrical, 0-5 to 0*7 mm. high, translucent, yellow, or yellow 

 above and orange-red below. Columella none. Capillitium a 

 dense network of pale yellow threads or flattened strands ; 

 lime-knots reduced to scanty deposits of lime in the expanded 

 axils of the branches. Spores pale violet, almost smooth, 

 7 to 9 /x diam. 



PI. 199. — d. sporangia (Philadelphia) ; e. capillitium and spores ; /. spore. 



This species is closely allied to P. flavicomum (q.v.), but the distin- 

 guishing characters appear to be constant ; it has been found in several 

 States of N. America, in England, and in Portugal. 



Hab. On dead twigs. — Witley, Surrey (B.M. 2140) ; Shropshire 

 (B.M. 2141) ; Portugal (B.M. 2142) ; Philadelphia (B.M. 1893). 



23. P. Maydis Torrend Plore des Myxomycetes, 193 (1909). 

 Plasmodium ? Sporangia globose or obovoid, 0-4 to 0-6 mm. 

 diam., stalked, scattered or gregarious, bright yellow or dull 

 yellowish-buff, rugulose or scaly, often rufous below ; sporan- 

 gium-wall j r ellow and membranous above, usually firm and 

 redder at the base, containing abundant deposits of yellow 



