38 
ENDOSPOREiE. 
[PHYSARUM. 
KEY TO THE SPECIES OF PHYSARUM. 
A. Sporangia stalked (occasional sessile forms) : — 
A. Stalks charged with lime throughout — 
a. Capillitium lax — 
Stalk white, sporangia grey, lime-knots large, 
white. 1. P. leucopus 
Stalk white, sporangia tawny yellow, lime-knots 
large, white. 8. /-•. melleum 
Stalk and sporangium yellow-olive. 7. P. variabile 
h. Capillitium rigid, persistent — 
Stalk white or brownish, sporangium white, lime- 
knots small, white. 2. P. globuliferum 
Stalk, sporangium, and lime-knots red. 
3. P. pnlc/irijjes 
Stalk, sporangium, and lime-knots mouse-brown. 
4. P. murinum 
Stalk, sporangium, and lime-knots purple. 
» ^. P. pulcherrivium 
Stalk, sporangium, and lime-knots yellow ; robust. 
6. P. citrinum 
Stalk, sporangium, and lime-knots straw-coloured; 
slender. 9. P. tenerum 
Stalk and sporangium white, capillitium with a 
central ball of lime. 10. P. covipactum 
B. Stalks without lime or with deposits in the wall only — 
a. Lime-knots purple-red, sporangium rose-red. 
W. P. roseum 
h. Lime-knots and sporangia violet-purple. 
12. P. Neiotoni . 
c. Lime-knots orange, sporangium mottled, blue and 
red 13. P. psittacinicm 
d. Lime-knots yellow or orange, sporangium grey or 
yellow — 
Sporangia subglobose, capillitium lax, lime-knots 
fusiform. 14. P. virids 
Sporangia undulate, capillitium lax, lime-knots 
fusiform. 16. P. pohjmorphum 
' Sporangia subglobose, capillitium subrigid, per- 
sistent, lime-knots angular. 15. P. Berkeleyi 
Stalk penetrating the sporangium to four-fifths its 
height. 18. P. ^je?te<?-a^e 
