ARCYRIA.] 
ARCYRIACE/E. 
185 
K. JSTorg., Sop. iii. (1892), p. 11 ; Mass., Mon., p. 144. Arcyria 
intricata Rost., Mon., App., p. 37. Arcyria dictyonema Eost., 
Mon., p. 279 ; Cooke, Myx. Brit., fig. 195 ; Mass., Mon., p. 154. 
Heterotrichia Gahriellai Mass., Mon., p. 140. Arcyria macrosjwra 
Peck, in Rep. N. York State Mus., xxxiv., p. 43 (1881) ; Durant, 
in Bot. Gaz., xix., p. 89. 
Plate LXVI., B. — a. sporangia, x 20 ; ft. portion of sporangium-wall, 
X 600 ; c, d. threads of upper part of capillitium, x 600 ; e. thread of 
basal part of capillitium, x 600 (Englgjid) ; /. capillitium of type of 
A. Mctyonema Eost. x 600 (Germany) ; g. capillitium of type of Hetero- 
trichia Gabriellce Mass. x 600 (United States). 
This species varies considerably in the markings on the capillitium ; 
the network of a single sporangium may in some parts be conspicuously 
thickened on one side ; in other parts the threads may appear nearly uni- 
formly spinulose. In the type specime-n of A. dictyonema Rost., from 
Freiburg, in Strassburg Herbarium, the capillitium is spinose, principally 
on one side of the thread, with broken reticulation and spinules on the 
other part ; there are numerous free branches with clavate or pointed 
ends ; except that the spines are more developed than usual, the markings 
do not differ from those frequently seen in typical A. ferruginea, of 
which it must be considered a form. The type specimen of Heterotrichia 
Gahriellai Mass., from S. Carolina (K. 838), differs from A. ferruginea 
only in the numerous pointed free ends in the upper part of the net 
of the capillitium ; the threads are flattened, very closely reticulate 
and spinulose, and in many places thickened on one side ; the spores 
measure 10 to 11 /x. The abundance or scarcity of free ends varies 
much in different gatherings of A. ferruginea, and is not a sufficient 
character on which to base a species. A. mcccrosjmra Peck appears 
from the description to differ in no respect from typical A. ferruginea. 
Hah. On dead wood. — Leytonstone, Essex (L:B.M.153) ; Lyme 
Regis, Dorset (L:B.M.153) ; Leighton, Beds (L:B.M.153) ; Henllys, 
Anglesey (B. M. 1130) ; France (K. 921) ; Germany (B. M. 727) ; 
Norway (Christiania Herb.) ; Australia (K. 848) : Mass., U.S. A 
(L:B.M.153) ; S. Carolina (B. M. 966). 
2. A. versicolor Phillips, in Grev., v., p. 115 (1877). Plas- 
modium? Total height 2*5 to 3 mm. Sporangia pyriform or 
clavate, shortly stipitate or sessile, gregarious, 1 to 2 mm, diam., 
more or less shining, yellow or olivaceous-yellow ; sporangium- wall 
membranous, persistent except at the apex, yellow, papillose on 
the inner side. Stalk membranous, 0'2 mm. long, yellow-brown, 
fiUed with spore-like cells, arising from a well-developed hypo- 
thallus. Capillitium an elastic network of freely branching 
yellow threads, 4 to 6 /x diam., triangular or oval in section, 
either uniformly spinulose and marked with broken reticulation^ 
or one side thickened and marked with transverse bars; the 
threads arise from the tube of the stem, and are not attached to 
the sporangium -wall ; free ends shortly pointed. Spores yellow, 
smooth, 8 to 10 /X diam.— Mass., Mon., p. 149. Arcyria vitellina 
Phill., ;.c., p. 115. 
^inn^ ^■^^^h- sporangia, x 20 ; h. portion of sporangium-wall, 
X 600 ; c. capillitium and spore, x 600 (California). 
