42 ENDOSPOREAE [PHYSARTJM 



Stalk, sporangium, and lime-knots purple. 



9. P. pulcherrimum 



Stalk, sporangium, and lime-knots yellow ; robust. 



10. P. citrinum 



Stalk, sporangium, and lime-knots straw-coloured ; 

 slender. 11. P. tenerum 



Stalk and sporangium white ; capillitium with a 

 central ball of lime. 12. P. compactum 



Stalk ochraceous, often absent ; sporangium white, 

 ovoid or cylindrical, with a long pseudo-columella. 



13. P. mutabile 



b. Stalks without lime, or with deposits in the wall only — 

 (See also 13). 



a. Lime-knots purple-red ; sporangium rose-red. 



14. P. roseum 



/?. Limo-knots and sporangium violet-purple. 



15. P. Newtoni 



y. Lime- knots orange; sporangium glossy, mottled blue 

 and red ; stalk red or orange. 16. P. psittacinum 



8. Lime-knots orange ; sporangium bronze ; stalk black ; 

 spores reticulated. 17. P. dictyospermum 



e. Lime-knots yellow or orange ; sporangia yellow, 

 orange, or grey — 



Sporangia subglobose or lenticular, on slender stalks ; 

 capillitium lax ; lime-knots fusiform. 



18. P. viride 



Sporangia subglobose on stout stalks ; linie-knots 

 pale yellow, angular or branching. 



19. P. Bethelii 



Sporangia contorted, stalked, usually clustered ; 

 capillitium lax ; lime-knots fusiform. 



20. P. polycephalum 



Sporangia subglobose, yellow or iridescent-bronze ; 

 stalks red-brown ; slender capillitium persistent ; 

 lime-knots angular, small. 21. P. flavicomum 



Sporangia globose on slender yellow stalks; lime- 

 knots angular. 22. P. galbeum 



Sporangia subglobose or obovoid, yellow with a 

 reddish base ; lime-knots angular, large. 



23. P. Maydis 



