BREFELDIA.] AMAUROCH^TACE.E. 135 



SPECIES NOT MET WITH IN THE QUOTED COLLECTIONS. 



2. A. minor Sacc. & Ellis, in Michelia, ii., p. 566. Effused, 

 varying, oblong, adnate-applanate, the margin almost naked, 

 externally clay-colour, very minutely punctate, internally blackish. 

 Gapillitium threads filiform, sparingly branched and anastomosing, 

 very pale brown. Spores blackish, minutely warted, then quite 

 smooth, 15 /x diam. 



Hal). On twigs. Utah. 



This description suggests an imperfect specimen of DictydicBthalium 

 plumbeum. 



Genus 21. BREFELDIA Rostafinski, Versuch, p. 8 (1873). 

 ^Ethalia 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, sometimes forming imperfect 

 sporangium-walls and central columella3. Capillitium of numerous 

 horizontal threads, uniting at the surface of the sporangium to 

 form many-chambered vesicles. 



1. B. maxima Host., Yersuch, p. 8 (1873). Plasmodium white, 

 in rotten stumps of fir, beech, etc. ^thalia 2 to 16 cm. broad, 

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

 branching sporangia O3 to 0*5 mm. diam., extending upwards 

 from the spongy basal tissue, which is continued among them 

 as irregularly branching, purple-brown membranous folds, usually 

 forming distinct rigid columellse. Capillitium consisting of 

 numerous threads radiating from near the central part of the 

 sporangium ; 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 slightly attached in clusters 

 of three or four by a fragile membrane. The vesicles are of firm 

 structure, often containing a spore in several of the chambers, 

 w T ith no appearance of forming part of the sporangium-wall, 

 except where they occasionally coalesce in fewer or greater numbers 

 to form vertical scalariform strands. Spores purplish-brown, 

 minutely spinulose, 9 to 12 ^ diarn. Mon., p. 213; Cooke, Myx. 

 Brit., p. 53; Mass., Mon., p. 91; Macbride, in Bull. Nat. Hist. 

 Iowa, ii., p. 389. Iteticularia maxima Fr., Syst. Orb. Yeg., i., 

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

 p. 451. 



Plate LI., A. c. 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 a? is seen a 

 scalariform strand, formed by vertical union of a row of vesicles, x 50 ; 

 cl. capillitium threads and vesicles, x 180 ; c. spore, x 600 (England). 



