48 



in the upper part of the branches partly and apparently more often 

 densely crowded near the apex, or forming a border around the 

 branches at or a little below the apex. They even sometimes are 

 so densely crowded, that the roofs become angular, and in all 

 rather resembling those of L. dimorphum, but smaller and, as in 

 the latter, in a younger stage easily confounded with conceptacles 

 of other species. They are slightly convex and little prominent, 

 but never, so far as I have seen, flattened in the central portion, 

 as often is the case in the named species, the roof 300 — 350 [i 

 in diameter, seldom more. The sporangia are four-parted, 120 — 

 180 fj. long and 45 — 80 p. broad. Among numerous specimens 

 collected in summer only some few were furnished with these 

 organs. 



The named conceptacles at length become overgrown, com- 

 monly to be found only in the peripherical portion of a branch, 

 but always in less numbers than in the preceding species, and in 

 several specimens examined I have not found older grown-in or- 

 gans of this kind. This probably is in part caused thereby, that 

 the roof is rather thin and easily dissolvable, though apparently 

 thicker than in L. dimorphum, and often falling away. I more 

 frequently met with overgrown conceptacles effaced by local forma- 

 tions of tissue than in the named species, and in the same manner 

 as mentioned under this one. Besides, the conceptacles of anthe- 

 ridia and cystocarps appear not to be found in the same individual 

 bearing conceptacles of sporangia. These organs do not as a rule 

 become overgrown, although now and then only the upper part 

 of the roof falls away at maturity, the rest perhaps partly being 

 filled with local formations of tissue partly not, and the whole 

 covered with a new thickening layer of the frond, as remarked in 

 regard to the conceptacles of sporangia. 



The cystocarpic conceptacles are conical, acute, 400 — 500 /* 

 in diameter at the base. They are up to 300 p. high, with a single- 

 orifice, but the upper portion easily falls away, then forming a 

 low, nearly hemispherical or sometimes even convex conceptacle,, 

 in the middle intersected with a coarser canal about 30 p in dia- 

 meter, and at maturity this middle portion first falls away, and 



