Fungi, by M. J. Berkeley.) FLORA OF TASMANIA. 267 
The only species is universally distributed, and is the pest of hothouses, from its abundant dusty spores. (Name 
from aan, soot.) 
l. ZEthalium septicum (Fr. Syst. iii. p. 93). 
Has. Amongst fallen leaves, Gunn. 
Gen. XLIV. DIDERMA, Pers. 
Peridium duplex, exterius crustaceum, discretum, glabrum, fragile, dehiscens; interius tenerrimum, 
membranaceum, evanescens. ` Ffocci vagi, versus basin adnati, aut sepius columelle affixi interque sporas 
compactas repentes, raro latentes. 
The only Tasmanian species in the collection is one of the commonest European forms. Probably others will 
reward future researches. (Name from is, double, and deppa, a skin.) 
l. Diderma vernicosum (Pers. Syn. p. 165). 
Has. On sticks, Archer. 
Gen. XLV. DIDYMIUM, Schrad. 
Peridium membranaceum, tenue, irregulariter dehiscens aut fatiscens, tectum cortice (peridio externo 
non discreto) adnato in squamulas furfuraceas aut villum farinosum mox fatiscente. Flocei vagi, peridio 
adnati, inter sporas repentes. 
Here again we have one of the commonest European forms. (Name from &óvpos, double.) 
l. Didymium costatum (Fr. Syst. Myc. iii. p. 118). 
Has. On sticks, moss, etc., Archer. 
The stem is longer than in the state described by Fries, and the peridium umbilicate. Columella white; 
flocci dark. 
Gen. XLVI. PHYSARUM, Pers. 
Peridium simplex, membranaceum, nudum, irregulariter dehiscens. Columella nulla. Spore floccis 
peridio adnatis intertexte. 
The perfect, simple, delicate peridium, combined with the absence of a columella, at once characterize this 
genus. The Tasmanian representatives are altogether European. (Name from vraw, to puff up.) 
1. Physarum nutans (Pers. Syn. p. 203). 
Haz. On Sterea, etc., Archer. 
Peridium white. Stem tawny. 
2. Physarum hyalinum (Pers. Syn. p. 170). 
Has. On moss, etc., Archer. i 
The peridium is globose, and the stems pale, but of the same nature as those of P. hyalinum, though agreeing 
in colour with those of P. utrieulare. The two species are probably mere forms of one. I have, in fact, undoubted 
P. hyalinum, from Fries, marked P. utriculare. Both belong to the genus Badhamia, should it be found that it is 
really distinct from Physarum, or, in other words, if Physarum has ever solitary spores. 
Gen. XLVII. CRATERIUM, Trentepohi. 
Peridium simplex, operculatum. Capillitium e floccis subloculosum. 
