CLASTODEBMA.] 
STEMONTTACEilD. 
133 
the ultimate branches attached singly or two or three together 
to the membranous plates of the sporangium-wall. Spores pale 
lilac, smooth, 7 to 10 diam.— Christ. Vidensk. Forh., No. 4(1882); 
Bidr. K. Norg., Sop. iii. (1892), p. 7. Orthotrichia microcephala 
Wing., I.e. ; Mass., Mon., p. 109. 
Plate L., B.—a. sporangia, x 20 ; h. apex o£ stem, capillitium, and 
spores, X 280 ; c. part of capillitium from another sporangium, x 280 
(United States) ; d. capillitium with expanded membranous plates, x 280 
(Norway) ; e. spore, x 600 ; /. sporangium, x 20 (Norway). 
This species was discovered by Prof. Blytt in 1879, near Christiania, 
growing on dead Polyporus. In the United States it has been re- 
peatedly found, and described by Mr. Wingate as OrtJiotrichia micro- 
cejjhala. In these gatherings the threads anastomose more freely than 
in the Norwegian specimen, and the disc-shaped fragments of the 
sporangium-wall are usually less pronounced. In some sporangia, 
however, they agree essentially with the type kindly submitted for 
examination by Prof. Blytt, and it cannot be doubted that they are 
the same species. 
Hab. On dead wood. — Norway (Christiania Herb.) ; Borneo 
(L:B.M.10O) ; Philadelphia (B. M. 874) ; Ohio (L:B.M.100). 
ALLIED GENERA NOT MET WITH IN THE QUOTED COLLECTIONS. 
RACIBORSKIA Berl., in Sacc. Syll., vii., p. 400 (1888). Spor- 
angia naked, globose, stipitate. Stem produced into a columella 
one-third or half the height of the sporangium, bearing at its apex 
short, slender, secondary columellse, which branch again in a 
similar manner, the ultimate branches combining to form a net- 
work without free ends. — Rostafinshia Racib., in Rozpr. Mat. 
Przyr. Akad. Krak., xii., p. 77 (1884). 
1. R. elegans Berl., I.e. Sporangia naked, globose, 0*5 mm. 
broad. Stalks erect, 1 to 2 mm. high, subulate, furrowed, black. 
Columella cylindrical, 8 to 10 yu, wide. Capillitium blackish- 
violet, the branches becoming gradually more slender outwards, 
the ultimate branchlets furnished with scattered spines. Spores 
dull violet, 9 to 10 diam. — Rostafinskia elegans Racib., ^.c.,p. 78. 
Hah. Botanical Gardens, Cracow. 
This description applies to Comatricha obtusata, in which the 
columella frequently branches in a dichotomous manner. 
ECHINOSTELIUM de Bary, in Rost., Versuch, p. 7 (1873). 
Sporangia stalked, minute, naked, without columella, Capillitium 
arising from the apex of the stalk, its branches forming a 
network. 
1. E. minutum de Bary, in Rost., Mon.; p. 215, figs. 53, 54, 
58, 68. Sporangia scattered, stipitate, globose, 37 to 57 /x diam., 
naked, whitish. Stalk 0'28 to 0-46 mm. high, brownish below, 
pale above. Capillitium of curved branching threads, with acute 
free branches. Spores entii^ely colourless, 6*7 to 8-3 /x, diam. 
Hab, Frankfort-on-Maine. 
