278 



commenced to branch, producing usually alternating branches at their distal end. 

 The following day a great number of the sporelings had produced a multicellular 

 monostromatic disc arising by further branching and fusing together of the branches, 

 and being terminal on a shorter or longer filament. After ten days the germ discs 

 were larger, some of the cells were divided by transversal walls, and several hairs 

 were given off from the upper surface. Some sporelings continued growing as long 

 unbranched filaments, but producing no disc; they were growing obliquely upwards 

 against the light. It is probably the want of contact with any solid substratum 

 which has caused the absence of a disc. The cultures were continued during up 

 to a month. The sporelings showed at the end of that time no essential differences; 

 they were only somewhat larger, having increased by marginal growth and cell- 

 divisions, and most of the cells were divided by a horizontal 

 wall, which may signify that the upper cell formed may be the 

 mother-cell of a vertical filament as described by Kuckuck, but 

 these filaments were not yet formed in their definite shape. 

 Numerous hairs were frequently produced by the disc. Fronds 

 emerging from the discs were not observed; they are probably 

 Fig. 201. only produced in the following year, the plant wintering probably 



Gioiosiphonia capiiiaris. jn the disc-shapcd Stage. The outline of the discs is nearly 



Partof transversal section . n • i i i x>i 



of frond with antheridia. orbicular. The number oi the cells in the basal germ filament 

 is rather variable ; usually it is small, and the filament may be 

 wanting, the branches continuing to the spore-cell. — A similar formation of the 

 germ disc, not from the si)ore-cell but from the germ-tube produced by it, is known 

 also for other Floridese, e. g. Dudresnaya (Killian, Entw. ein. Florid. Zeitschr. f. Bo- 

 tanik. VI, 1914, p. 287). 



The antheridia are, as shown by Bornet and Thuret (1. c. p. 42) found in spots 

 scattered on the plants which bear the carpogonia. They are oblong or obovate, and 

 are produced by transversal divisions of narrow cells covering the surface of the 

 plant. These cells branch, being divided by oblique walls (fig. 201). 



Regarding the development and structure of the cystocarps, reference may be 

 made to the important paper by Oltmanns in 1898 (see also 1904) where it was 

 proved that the double fertilization, presumed by Schmitz for this plant, do not 

 take place. 



The tetrasporangia were unknown to J. Agardh, as late as in 1876 (Epicrisis p.ll5) 

 although they were described by Ekman in 1856 and by Areschoug in 1875. They 

 are, according to the named authors, cruciately divided, though often very irregu- 

 larly; the sporangia-bearing specimens are much branched above, bearing dense 

 bushes of branches. Such specimens were found at Christianssund on the west 

 coast of Norway in August, later on the coast of Bohuslan in June by Kylin. On 

 the Danish shores, sporangia-bearing specimens have never been found. AH the 

 specimens examined (nearly 200) were sexual plants. 



The species occurs on stones in exposed places in small depths (1 — 5 meters). 



