328 
might attain a considerable length without branching, but on meeting a solid 
body they had fixed themselves to it and produced numerous branches partly 
adhering to the same body (fig. 245 B). 
The antheridia always occur on par- 
ticular male specimens. They form small, 
often hemispherical cushions on the 
upper branchlets; they are usually seat- 
ed, in analogy with the sporangia, on 
the upper side of the lower joint of the 
branchlets, near its upper end, but, as 
shown by THURET, two or three cushions 
are frequently seated under one another 
and these may be fused together. The joint 
may thus be occupied in its whole length 
or nearly so by a long compound an- 
theridial cushion, and the joint is then 
Callithamnion corymbosum. Antheridial cushions. %0:1. usually more or less recurved by epi- 
nastic growth and bears no vegetative 
branch. When the production of antheridia is very abundant, they occupy not only 
the branchlets but also the mother axes. The cushions consist of much branched short 
branch-systems, the upper cells of which are the antheridia (spermatangia) (fig. 246). 
With regard to the position and the develop- 
ment of the procarps and the cystocarps reference 
may be made to the quoted papers of THURET 
(1878, pl. 34 and 35), OLTManxs (1898) and N 
Kyrın (1907, p. 166). A! NM) / 
As mentioned by earlier observers, the te- NÆS IN 187, 
trasporangia are seated on the inner side of the AN / / nr ISG 
.. À j j 
upper branchlets. on the lower joint. usually at \/ { )\ / 
its upper end. The first branch of the second order OS i} 
£ ER 2 N NY, | 
having a transversal position, the sporangium | | NY 
then forms a right angle with this branch. The Il 2 | / 
an GE single or a younger SRE KE 
ppears under the first formed, sometimes in an FE 
oblique direction under it or nearly beside it 
Fig. 247. 
(fig. 247 4). A third sporangium may rarely be Callithamnion corymbosum. Tetrasporangia. 
found under the second. In rare cases the spo- 210 : 1. 
rangium is inserted in the middle of the joint 
(fig. 247 B, C); in the case shown in fig. 247 C, a second sporangium is seated over 
the first formed. — As shown by THURET (1878, plate 35 fig. 14), the sporangia 
open by a transversal split near the upper end of the sporangium; the upper part 
of the wall then forms a lid fixed by a hinge. At the discharge, which was once 
