1917] 
: BURT—MERULIUS IN NORTH AMERICA 345 
arated here and there to form the spongy interspaces, and 
with (2) a very dense hymenial layer 120 д thick; spores col- 
ored, paler than the hyphae, even, flattened on one side, 32 
и, none found attached to basidia. 
On sticks, mosses, ete. Cuba. 
Fructification of Ше cotype has Ше free portion 14 em. 
broad, about 2 em. long, attenuated at base to 1 em. long, and 
the resupinate portion of equal area, 142 em. 
The spore characters are those of a few spores which were 
squeezed from the surface of the hymenium of sections and 
may have been foreign, for no spores were demonstrated on 
basidia. The reflexed form, dark color, remarkable spongy 
structure, very dense hymenium, nearly even for the greater 
portion of its area and with minute shallow pits near base, 
are characters which distinguish this species. 
Specimens examined: 
Cuba: С. Wright, 186, cotype (in Curtis Herb.). 
30. M. americanus Burt, n. sp. 
Merulius lacrymans var. tenuissimum Berkeley in Ravenel, 
Fungi Am., 134. 1878; Grevillea 6:131. 1878; Saec. Syll. 
Fung. 6: 419. 1888.—Not Merulius tenuissimus Berk. & 
Broome, Linn. бос. Bot. Trans. 2: 62. 1883. 
Type: type distribution in Ravenel, Fungi Am., 134. 
Fructification resupinate, effused, membranaceous, sepa- 
rable, thin, fragile, not fleshy, drying Brussels-brown to bone- 
brown, the margin not thickened; hymenium gyrose-porose, 
with the folds growing out into raduloid teeth on an inclined 
substratum, the pores about 1-14 mm. in diameter and depth 
or half as deep; in structure 400-600 и thick, 
with (1) a layer 300-450 и thick next to the OO 
substratum, composed of loosely interwoven, 
thick-walled, rigid, nodose-septate, colored м americanus. 
hyphae 44-6 шіп diameter, and of hyaline oer a 
hyphae intermixed throughout, the latter Р 
sometimes granule-incrusted, and with (2) а narrow layer 
about 100-150 и broad, bearing the hymenium, composed of 
densely arranged, hyaline or nearly hyaline hyphae; no 
