108 A Monogmph of the Myxogastres. 



Raciborskia, Berl. 



Sporangia naked, globose, stipitate, stem elongated, entering 

 the sporangium as a columella from one-tliird to half its height, 

 bearing at the apex secondary, short, slender columellas, these 

 in turn divide in a similar manner to the primary columella ; 

 ultimate branches combined amongst themselves at every point 

 to form a network ; extreme branchlets not free but arcuately 

 combined with each other, 



Racihorslda^ Berlese, Sacc, Syll., vii., pt. I., p. 400. 



Bostafinskia, Racib., Myx. Crac, p. 9 (not of Spegazzini). 



Distrib. Poland. Species 1. 



Raciborskia elegans, Berl. 



Sporangia naked, globose, up to '5 mm. broad, stem erect, 

 1 — 2 mm. high, thickest at the base, then subulate-attenuated, 

 plicate, black ; columella half to one-third shorter than the 

 sporangium, cylindrical, 8 — 10 ju, thick; capillitium blackish- 

 violet, exterior threads exceedingly thin, not free ; the extreme 

 branches furnished with scattered spines; spores 9 — 10 yi 

 diameter, obscure violet, aculeate. 



RacihoTsJda elegans, Racib., Myx. Crac, p. 10, fig. 5. 



Poland. 



Raciborski considers that the present species is allied to 

 Rostafinski's genus Echiiwstdiwin. He also inclines to the idea 

 that the genus Oiihotricha may prove to be identical with his 

 Bacibm-slda (= Bostafinskia, Racib.).* 



EcHiNOSTELlUM, De Bary. 



Sporangia stipitate, columella absent, capillitium originating 

 from apex of stem, tlireads arcuate, combined to form a loose 

 network, furnished with numerous spine-like free arms. 



EcMnostdium, De Bary, in Rost., Mon., p. 215; Cooke, Brit. 

 Myx., p. 53. 



* Hedwigia, March and April, 1889. 



