Mon 
mid-rib remains. In exposed localities the disorganisation may begin earlier and the 
mid-rib may be denudated in September, whereas in sheltered localities, e. g. in 
the belts the laminæ keep till the next spring, having then a brownish colour. 
W776 
SIT Bo) 
ds So? Do SC 
Bie ES a 
SUG CD S \) 
Fig. 443. 
Delesseria sanguinea. Parts of 7 mm long plantlet, primary shoot. A, apical part Showing cell-divisions. B, marginal 
part showing secondary, variously orientated apical cells. C, lateral veins and secondary pits. 560 : 1. 
The fertile folioles arise in the autumn as adventitious shoots on the mid-ribs 
of the leaves from the foregoing winter. The development and structure of the or- 
gans of fructification has been thoroughly described by SvepeLıus and Kyrın and 
will not therefore be mentioned here. The three kinds of fructification always occur 
in separate individuals. The antheridia-bearing leaflets were met with in September 
and October; they reach a length of 5 mm. The procarp-bearing leaflets produce 
a great number of procarps situated on the mid-rib, but one eystocarp only is devel- 
oped in each shoot. Ripe cystocarps were met with in January and may certainly 
61* 
