470 MR. G. MABBEE—REDESCRIPTIONS OF 
blackish-green, 1-3 cm. diameter ; ascophore parenchymatous, the 
cortical cells hexagonal, 28-36 u diameter; asci cylindrical, apex 
rounded, blue with iodine, as are also the paraphyses when old, 
about 225x16-17; spores 8, l-seriate, hyaline, continuous, 
smooth, often 2-zuttulate, broadly elliptical, ends obtuse, wall 
rather thick, 20-23X13-14 p; paraphyses numerous, stout, 
becoming gradually thicker and brown upwards, tips 7-8 u thick, 
septate, longer than the asci. 
Psilopezia nummularis, Sacc. Syl. viii. n. 615. 
Psilopezia myrothecioides, Berk. & Broome, Not. Brit. Fung., 
in Ann. & Mag. Nat. Hist. ser. IV. vol. xv. (1875) p. 39, t. 2. 
fig. 5; Sace. Syll. viii. n. 617. 
Rhizina myrothecioides, Massee, Brit. Fungus-Flora, vol. iv. 
p: 455. 
-Exsicc. Ellis, N. Amer. Fung. n. 568. 
On damp, rotten wood. United States—Ohio (Zea, n. 243, 
with query, * Myrothecium P”); Pennsylvania (Michener, 
n. 3530); S. Carolina (Ravenel, n. 2959); New Jersey (Ellis) 
(called Psilopezia myrothecioides). Scotland (Rev. J. Fergusson). 
When old the margin becomes bald, and sometimes becomes 
slightly raised from the substratum. 
A careful comparison of the types of P. nummularia and 
P. myrothecioides shows that the two are identical in structure, 
differing only in the colour of the dise, consequently the last 
named must be reduced to a synonym of the first named. The 
plants appear to increase in size by constant extension of the 
margin, as in the genus Corticium. The genus Psilopezia, 
established by Berkeley (Lond. Journ. Bot. vol. vi. (1849) p. 325), 
resembles superficially the genus Phillipsia, but is distinguished 
by the parenchymatous structure of the ascophore, and the stout, 
clavate, brown paraphyses, which are longer than the asci. On 
the other hand, there is an absolute agreement between the 
present genus and RA¿zina, unless we limit the last-named genus 
to R. inflata, Quél., which would then differ in the presence of 
continuous thick-walled brown tubes in the hymenium differing 
in structure from the paraphyses. 
RHIZINA sPONGIOSA, Berk. d Curt. in Journ. Linn. Soc. 
( Bot.) vol. x. (1869) p. 364; Sace. Syll. viii. n. 184. (Pl. XVII. 
fig. 33.) 
Sessile, sometimes narrowed into a very short stem-like base, 
