MUSCI. 
3^9 
irichum Lyelli and ohtusifolium ; in O. phyllanthiim tufts of club-shaped protonemal 
filaments with short cells arise at the apex of the leaves ; and the same phenomenon 
occurs in Grimmia irichophylla^ Syrrhopodon, and Calymperes. In Oncophorus 
glaucus a dense felt of interlacing protonema-filaments is formed at the summit 
of the plant where the reproductive organs are produced, which arrests its further 
growth, and hence produces at a later period new clumps of young plants. In 
£uxbaumia, especially B. aphylla, the marginal cells of the leaves form a pro- 
tonema enveloping them as well as the stem with its filaments. Lastly, even 
Fig. ■2e^x.~Tetraphis pelhicida; A a plant producing gem- 
mae (natural size) ; B tlie same, magnified ; y the cup in which 
the gemmae are collected ; C longitudinal section through the 
summit of the plant, b the leaves of the cup, Ä'the gemmae in 
various stages of development ; the older ones are forced off 
their stalks by the later growth of the younger ones, and forced 
over the side of the cup ; D a mature gemma (X 500), consisting 
at the margin of one, in the centre of several layers of cells. 
Fig. 252. — Tetraphis pelhicida ; A, b a. gemma, detached 
from its stalk at a. the protonema-filament x has been formed 
by the growth of a marginal cell of the gemma, and the flat 
structure / as a lateral outgrowth from the protonema ; this has 
also put out root-hairs 7u, lu' , -w'' (x 100) ; B, p a flat protonema 
from the base of which a leaf-bud K and root-hairs w, iv' have 
sprung ; the base of the protonema often puts out a number of 
new flat protonemata before a leaf-bud is formed. 
detached leaves, if kept moist, may emit a protonema, as for instance those of 
Funaria hygrometrica ^ 
Gemmce, which, like those of the Marchantieae, are stalked fusiform or lenti- 
cular cellular bodies, occur in Aulacomnioji androgynum at the summit of a leafless 
elongation of the leafy stem (^Pseudopodium) ; in Teiraphis pellucida enveloped by an 
elegant cup composed of several leaves, out of which they subsequently fall. These 
^ [It has been shown by Pringsheim (Jahrb. für wiss. Bot. XI) and by Stahl (Bot, Zeit. 1876) 
that the sterile cells of the sporogonium and of the seta may give rise to protonema.] 
B b 
