136 ENDOSPORE.E. [BREFELDIA. 



The complex structure of the capillitium is difficult to follow in 

 the lower part of the ssthalium ; towards the surface the sporangia 

 are often separated from each other by a narrow interval. The sides 

 of the sporangia are then seen to glitter with the numberless vesicles 

 of the capillitium. The threads penetrate the adjacent sporangia to 

 the distance of 0'07 to (H mm., or about half the radius. The entire 

 length of the threads, including the central vesicle, is 0*15 to 0'23 mm. 

 The spores in the central part of the sporangium do not seem to be 

 traversed by any threads. In the lower strata the threads are some- 

 times attached at each extremity to folds of the membrane arising 

 from the spongy base ; but the rigid collumellse, throughout the upper 

 part at least, appear to be free from the capillitium. 



Hob. On dead wood. Lyme Regis, Dorset (L:B.M.102) ; Darenth, 

 Kent (B. M. 1110); Wanstead, Essex (L:B.M.102) ; Luton, Beds 

 (L:B.M.102) ; near Birmingham (L:B.M.102) ; Boynton, Yorkshire 

 (B. M. 1159); France (Paris Herb.); Sweden (K. 781); Germany 

 (Strassb. Herb.) ; Mass., U.S.A. (L:B.M.102) ; Iowa (B. M. 1020). 



RostafinsJcia austral is Speg., in Ann. Soc. Cient. Argent., x., p. 151 

 (1880), is described as forming an aethalium and having the surface 

 composed of softly velvety tomentum, breaking up into powdery 

 filaments ; the capillitium tubes of the lower stratum septate ; the 

 spores lilac, ovoid or irregular, 8 to 10 x 5 to 6 ju. It does not appear 

 to be a Mycetozoon. 



Cohort Il.LAMPROSPORALES. Spores variously coloured, 

 never violet. 



Subcohort ~L.ANEMINEjE Host, (extended). Capillitium 

 not forming a system of uniform threads; either wanting, or 

 represented by modifications of the sporangium-wall, which may 

 be perforated or laciniated in sethalioid sporangia, or produced 

 into tubular extensions in exceptional forms in the order 

 Tubulinaceae. 



Order I. HETERODERMACE.E Host, (extended). Sporangium- 

 wall membranous, beset with microscopic round granules (plasmodic 

 granules), and, except in Lindbladia, forming a net in the upper 

 part ; capillitium wanting ; spores 4 to 7 /x diam. 



KEY TO THE GENEHA OF HETERODERMACEsE. 



Sporangia sessile, compacted or sethalidid, the wall not forming a 

 net in the upper part. (22) LINDBLADIA 



ig. 30. Lindbladia Tubulina Fries. 



a. ^Ethalium. Natural size. 

 . Vertical section of sethalium. Magnified 6 times, 



I 



Fig. 30. 



