143 



Description of the spedes. The plant accords with L. dehi- 

 scens in its development, and the colour is neaiiy the same, only 

 a little darker and apparently less varying. The frond is at first 

 subspherical or neatiy hemispherical, at length assuming a cup- 

 shaped form like the named species, but frequently even less vaulted, 

 or occasionally plane or neaiiy plane. Pl. 20, fig. 1 — 3. In the 

 latter stage it is much rubbed in the part that has turned towards 

 the bottom, with the interwalls between the branch-systems visible 

 from this side. Pl. 20, fig. 4. Afterwards new formations of 

 tissue often cover the rubbing parts of these older and partly de- 

 nudated branch-systems, from which then new branches here and. 

 there are developed (pl. 20, fig. 5), or even covering the whole 

 lower side of the plant. Pl. 20, fig. 6. Cup-shaped specimens go 

 up to about 15 cm. in diameter and 1.5—2 cm. in thickness. It 

 is branched in an irregular subdichotomous manner, and the bran- 

 ches are densely crowded, in the lower part more or less anasto- 

 mosing and below the apex often furnished. with small wart-like 

 or short branch-like processes, occasionally showing a tendency 

 to form very small bundles. They are frequently rather straight 

 and fastigiate, terete and neaiiy cylindrical, with obtuse or slightly 

 spherically thickened ends, about 1 mm. thick, partly less partly 

 a little more. 



In a longitudinal section of a branch the inner cells of the 

 more or less distinct cup-shaped layers of tissue are rectangular, 

 or often neatiy square, about 9 — 12 ,u. long and 6—8 //. thick. 



The organs of propagation are unknown. I found some con- 

 ceptacles of cystocarps in a younger specimen, and these rather 

 resemble those in L. clehiscens, though frequently larger and more 

 acute and apparently not yet fully developed, but I do not know 

 whether this specimen really belongs to the present species. Nor 

 did I find overgrown conceptacles of sporangia in the specimens 

 examined and I, therefore, refer it to the section Evanidæ; howe- 

 ver, on the other hand it appears rather probably, that these organs 

 in fact grow down into the frond, but the not unlikely are seldom 

 developed in older individuals, or not occurring in the same indi- 



