94 - REVUE BRYOLOGIQUE. 
For in some Sarcoscyphi with a distinct monophyllous perianth 
— e. g. in A. olivacea mihi — the calyptra is inferior, and 
bears the sterile pistillidia on its dome-fike apex. M. con- 
cinnata (Ligbhtf.) is the only species TI have examined which 
seems to possess both forms of calyptra, the pistillidia in 
some flowers growing on and about its base alone, but in 
others spread over it to its very apex. : 
1 need hardly remind my readers that the absence of a 
monophyllous perianth — owing to the anthophyls being 
more or less free at maturity — has been considered sufii- 
cient ta constitute a distinct genus, variously named, Cesia 
by Gray, Acolea by Dumortier, and Gymnomitrium by Nees (1). 
t is plain from what precedes , that there is no such genus, 
dependant on that negative character alone ; any more than 
among mosses a genus could continue to exist, founded 
solely on the absence of a peristome , as in the Gymnostomum 
_ of Hedwig. I had already said, in my ’Musci and Hepa- 
ticæ of the Pyrenees’ (1849), « il would perhaps be more 
logical to consider Gymnomitrium as a section or subgenus 
of Sarcoscyphus » : an opinion which ulterior observation 
and reflection has confirmed and strengthened. It is true 
that the first species refered to Gymnomitrium had a peculiar 
habit, dependant on the densely-packed, cochleato-concave, 
brittle and subscariose foliage ; but in recent times several 
minute species bave been discovered, and tackcd on, some to 
Gymnomitrium , some to Sarcoscyphus , according to the 
absence or presence {real or supposed) of a monophyllous 
perianth ; although nearly all have distinctly the habit and 
texture 6f normal Sarcoscyphus. One species, which I bave 
not seen, viz. Gymn. condensatum Angstr., has (according to 
 Lindberg ,  Musci Scandin., no 166), the foliage of Gesia 
(Gymnomitrium) but the tubular adherent perianth of 
Marsupella. His words are : « Configuratione colesulæ est 
vera Nardia, sed habitum, fragilitatem, formam , marginem 
hyalinum, imbricationem densissimam , etc., foli..…....., ut in : 
proxima GC. coralÿoidi, quacum fere semper confusa, pos- 
sidet, » For this anomalous species he has created the 
_ subgenus Nardio-calyx, of Cesia ; instead of recognising in it 
(what it really is) a perfect link between the two groups, and 
à proof that they constitute but one natural genus. ; 
In examining numerous involucres of some species recently 
referred to Gymnomitrium, 1 have come on an almost com- 
plete series of intermediate forms between the two supposed 
nera. Ï cannot give here all the evidence I have collected” 
nède «hé prior Cesu: R. Br the 1w6 names Del 
ymnomäurium of Corda had for its 1ype Jung. 
its Lype « 
