172 ENDOSPOREAE [BREFELDIV 



Genus 25.— BREFELDIA Rostafinski Versuch, 8 (1873). 

 Aethalium pulvinate, consisting of subcylindrical, somewhat 

 branched, and confluent sporangia, rising from a base of spongy 

 barren tissue, which is continued, chiefly among the lower 

 portions of the sporangia, in irregular folds ; imperfect 

 sporangium-walls and central columellae sometimes present. 

 Capillitium of numerous horizontal threads, uniting at the 

 surface of the adjacent sporangia to form many-chambered 

 vesicles. 



1. B. maxima Rost. Versuch, 8 (1873). Plasmodium 

 creamy white. Aethalium pulvinate, 2 to 30 cm. across, 

 5 to 10 mm. thick, purplish-brown, composed of elongated 

 branching sporangia 0-3 to 0-5 mm. diam., extending upwards 

 from the spongy basal tissue which is continued among them 

 as irregularly branching purple-brown membranous folds ; 

 distinct rigid columellae often present. Capillitium consisting 

 of numerous threads radiating from near the central part of 

 the sporangium, but free from the columella ; each thread 

 expands at the boundary of the sporangium into a many- 

 chambered vesicle, which is continued into a corresponding 

 radial thread of the adjoining sporangium ; the proximal ends 

 of the threads are connected in clusters of three or four by 

 a fragile membrane ; the vesicles are of firm texture, often 

 containing a spore in several of the chambers, occasionally 

 coalescing in fewer or greater numbers to form vertical 

 scalariform strands. Spores purplish-brown, minutely spin- 

 ulose, 9 to 12 /a diam. — Rost. Mon., p. 213; Mass. Mom, 91; 

 Macbr. N. Am. Slime-Moulds, 110. Dermodium inquinans Fr. 

 Symb. Gast. 9 (1817) ? Reticularia maxima Fr. Syst. Orb. Veg., 

 i. 147 (1825). Licea perreptans Berk, in Gard. Chron., 1848, 451. 



PI. 136. — d. subdiagrammatic view of portions of four columnar sporangia from 

 an aethalium ; each sporangium has a central columella, and is clothed on the surface 

 with numerous vesicles, from which short capillitium threads pass into the adjacent 

 sporangia ; at x. is seen a scalariform strand, formed by vertical union of a row of 

 vesicles ; e. capillitium threads and vesicles ; /. spores (England). 



The complex structure of the capillitium is difficult to follow in 

 the lower part of an aethalium ; towards the surface the sporangia 

 are often separated from each other by narrow intervals. 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 0'1 mm., or about half the radius. The entire 

 length of the threads, including the central vesicle, is 0"15 to - 23 mm. 

 The mass of spores in the central part of the sporangium is not 

 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 ; the rigid collumellae, throughout the upper 

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

 sometimes very large, and may wander from the place of emergence 

 to mature into aethalia one or two feet in length. In the field this 

 species often shows considerable resemblance to the confluent form of 

 a Stemonitis, a genus to which Brefeldia appears to be nearly allied. 



