Dixon: NEw MossEs FROM MALAY PENINSULA = 247 
the Trichosteleuam. T. singapurense has besides the papillae 
much longer leaf points. The leaf form and alar cells show it 
not to be an Isopterygium. Unfortunately the quantity is very 
small. 
ACROPORIUM Mitt. 
The genus as understood here includes the species of Semato- 
phyllum as employed by Brotherus, with the exception of a small 
group of autoicous species of the Section Chaetomitriella, 
which appear to me better placed in Trichosteleum. American 
writers usually retain the arrangement of the Musci Austro- 
americani, i.e., they include under Sematophyllum all the species 
of Acroporium and also those separated by most recent authors 
(Jaeger, Brotherus, etc.) as Rhaphidostegium. Fleischer, on 
the other hand, in his recent work distributes the Javan species 
of the aggregate genus over ten different genera. I must confess 
that on the whole I prefer—with a few slight exceptions—the 
middle course kept by Brotherus, especially as concerns the 
keeping apart Rhaphidostegium and Sematophyllum. United 
they form a very unwieldy genus, at least 400 species having 
been described in the two Sections; while Rhaphidostegium, if 
not easy to separate by well defined structural characters, is so 
distinct in habit that so far as I know there has never been any 
doubt as to the position of any species of the whole 400 or so as 
to the group in which it should ke placed, with the possible 
exception of two—R. saproxylophilum (C. M.) being placed 
among species of Acroporium in the Bry. Javanica, and R. 
Schwaneckeanum (C. M.) having been placed—for some obscure 
reason—in Pungentella (i. e., Acroporium) by C. Mueller himself 
in Hedwigia, 1898. 
As regards the name, I think it is clear that Fleiscker is cor- 
rect in restoring Mitten’s name Acroporium, in the place of 
Sematophyllum, the name retained by Jaeger, Paris, and Broth- 
erus. 
The genus Acroporium was validly published by Mitten in 
his List of Samoan Mosses in Journ. Linn. Soc., Bot., x, 182 
(1868), and the diagnosis makes it clear that it is used in the 
restricted sense, not including the species often placed in Rhaphi- 
dostegium, and already separated from Hypnum (or Stereodon) 
by Mitten in 1864. 
