52 Transactions British Mycological Society. 
relationship can exist between these two plants. I consider Cor- 
ticium Pearsonti as a distinct species which will reappear under 
the same conditions of habitat and temperature. 
CORTICIUM PEARSONII N. sp. 
Adnatum, tenuissimum; 20-50p crassum, in rimulis ligni 
cariosi latitans, ceraceo-pruinosum, grisellum, vix continuum, 
mox furfuraceo-granosum, in sicco lineolis crustaceis albis, 
eximie reticulatis constans. Hyphae hyalinae, dense intricatae, 
rarius distinctae; 2—2°5 w, tenuiter tunicatae, nodulis sparsis; 
hymenium basidiis et rarioribus hyphis sterilibus, aequilongis 
compositum ; basidia obovata, 9-15 x 5-6, 2-4 sterigmatibus 
demum arcuatis, usque ad 6» longis; sporae hyalinae, anguste 
clavulatae, lateraliter depressae vel subarcuatae, 4°5-6 x 1-5-2 
(—2°5) p. 
In rimulis trunci pinei pullulans, Locus Weybridge, Surrey. 
Sept. ad finem Octobris 1920; legit A. A. Pearson. 
The genus Heterochaete Pat. was established for species of 
Sebacina with erect emergences on the hymenium consisting of 
compacted sterile hyphae with 
or without cystidia. Hetero- 
chaete dubia, Bull. Soc. Mycol. 
Fr. XXV, p. 30 (1909), placed 
doubtfully in this genus, does 
not in fact belong to it. This 
species has no emergences com- 
posed of sterile hyphae but 
only projecting cystidia which 
brings it into a group of the 
Sebacineae analogous to Penio- 
phora. It is therefore logical 
to establish a section or sub- 
genus for thespecies of Sebacina 
with cystidia, as has been done 
for the Sebacineae with gloeo- 
cystidia. 
This new sub-genus Hetero- 
chaetella till now only in- gig. 2. Heterochaetella crystallina. 
cluded H. dubia with allied 1. Spores of the British specimen. 
forms or species which have 2. SP- of no. 15208. 
not yet been published, and * SP. Ot Pere 
which are distinguished by thespore and nature of the cystidium ; 
in H. dubia this is of the same type as in Peniophora glebulosa 
and in other forms, of the type found in P. subalutacea or 
cineracea. 
The new species, described below, is differentiated from the 
