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The species are distinguished by the thickness of the 
cortical layer surrounding the stem; this is in some species 
constituted of five layers of cells, in others of three layers, 
and in yet others of one layer only. This specific character, 
in conjunction with the form of the leaf, is sufficient to 
identify the few species as yet known in Tasmania. The 
capsule is nearly globose and is sessile on the seta or fruit 
stalk, and the mouth of the capsule is destitute of peristome 
or teeth. It is, notwithstanding, an elegant form, and can 
be easily examined with a pocket lens. The leaves are re- 
markable for their singular cellular structure, and each cell 
contains a formation which Robert M. Stark in his “ British 
Mosses ” designates “a spiral fibre.” 
Sus-OrRDER 3. BRYACEA. 
Section 1.. Fruit terminal. 
Tribe 1. PsHascmw. Earth Mosses—Genus 3.—Phascum. 
The plants of this genus arethesmallest of all mosses, and 
probably the smallest of all flowering plants, some of the 
species not exceeding the size of an ordinary pin’s head, roots, 
stem, leaves, and fruit included. All are perfect after their 
kind, and as varied and beautiful as flowering plants of larger 
growth and more easily observed. 
These tiny plants must be looked for on the beds of dried 
up pools and on clayey or chalky banks; it will even be 
necessary to kneel down with pocket lens in hand and care- 
fully examine the surface of the soil to detect the presence 
of some species. The capsule of Phascum bursts irregularly 
when ripe, and in this character it differs from all other 
mosses. The brightly coloured capsule, the intensely green 
leaves, the flowers, and the markea cellular structure 
combine to make this plant an interesting object for dark 
ground illumination with the microscope, one which may 
justly lead us to reflect on the mystic Vital Force, that of one 
primordial cell, developes, in its own peculiar way, and by 
two generations, into a minute but perfect Phascum plant ; 
and of another to all appearance exactly similar cell, in its 
own peculiar but very diverse way, into a giant Pine or 
Eucalyptus. 
