105 



part may thus become two or even three cells thick, as stated by Harvey Gibson 

 (Journ. of Bot. 1892 p. 104), but a real parenchymatous disc I have never seen. 

 From the basal layer numerous erect filaments appear, forming 6 mm. high clusters. 

 The filaments are usually 9 — 12 n thick, but the thickness may vary from 8 to 13 /i. 

 The cells are usually 2 — 4 times as long as broad (more rarely 1 — 5 times). The 

 cells contain a parietal chromato- 

 phore with a well developed pyre- 

 noid, very prominent in the inter- 

 ior of the cell ; sometimes the 

 pyrenoid is so large that the part 

 of the chromatophore in which it 

 lies reaches nearly to the part of 

 the same chromatophore on the 

 opposite side of the cell (fig. 34 F). 

 According to Kylin (1907 p. 118) 

 hairs rarely occur, a sporangia- 

 bearing branchlet terminating in 

 a hair instead of a sporangium. 

 I have never seen unicellular hya- 

 line hairs; on the other hand the 

 fertile branchlets were often found 

 tapering into very thin hair-like 

 filaments, the cells of which be- 

 come longer and thinner and de- 

 coloured upwards (fig. 34 C), as in 

 Ch. Thuretii. 



The sporangia are always sit- 

 uated on branchlets which are 

 more or less branched; the most 

 vigorous are repeatedly branched 

 and consist of at least 3 generations 

 of branches, the youngest of which 



Fig 34 



is situated on the mner side of the chantransia OauiesU. A and B. basal parts of plants growing on 

 foregoing, so that the branchlet gets the .stalk of LanUnaria digitata seen from aliove and from the side. 



, „ e f I A e ' ^ C—E, erect filaments with sporangia-bearing branclilets. F, three 



the lorm Ot a lan-Sliaped raSClCle. cells showing the chromatopliore (December). .1— ii 800 : 1, F 390 : 1. 



These branchlets are mainly placed 



in the axils of the branches, on the inner side of their undermost cell, but they 

 may also occur scattered on the sides of the principal filaments. In the first case 

 one fascicle only is placed in each axil , especially when the branchlet is well de- 

 veloped, but not rarely two less branched branchlets are placed the one over the 

 other (fig. 34 D), and there is then a resemblance with Ch. Thuretii; typical sporan- 

 gia-bearing fascicles are, however, always to be found on the same plants. I found 



I). K, I). Viilensk. Selsk. Skr., 7. H;L-l<ke, nntiirviilensk. <)(>' illiitliem. Af'il. VII. 1. 



14 



