KONGL. SV. VET. AKADEMIENS HANDLINGAR. BAND 20. N:0 5. 111 



of the second order, which are ovate or ovato-triangular in circumference, of pretty 

 equal size, very thin at the lower part of the side axis, somewhat denser upwards, 

 although even here they are thin. With these branch-systems of the second order 

 those systeras of the first order, that issue nearer the suinmit of the main stem, agree. 

 Branches of a higher order than the third are rare. The branches of the last order 

 are fine as a hair, and there is a great difference in thickness between branches of the 

 first and the second order. 



The summer and autumn plant of the first year presents the aspect shown by fig. 2. 

 This is produced by the upper branch-systems and all lower branches of a higher or- 

 der than the first in the spring plant, having fallen off either completely or so that 

 only the lowest basal parts remain. The frond accordingly consists here of the main 

 axis of the frond and the lower side-axes of the first order, all of which have increased 

 in solidity and thickness. 



Older sterile specimens in spring. The plant reaches a considerable size, at least 

 I — 2 feet high, very bushy. In ramification, older individuals agree with a plant of 

 the first year's growth, differing from it only by the ramification being raore decom- 

 pound. At the commencement of the new season, the organs of reproduction being 

 developed, new branch-systems spring out from the perennial portions, sometimes re- 

 sembling the primary branch-systems of the young plant, sometimes the whole plant 

 of the first year, and sometimes being even more decompound than this. 



Older individuals in autumn resemble younger individuals at the same time of the 

 year, differing only by being larger, more robust, and more decompound. 



Individual with antheridia, sporocarpia and tetrasporangia. I have found such 

 individuals only during winter, in the months of December and January. They agree 

 with the autumn plants, except in the surviving parts being more or less densely co- 

 vered with short, decompound branch-systems, sometimes single, sometimes gathered 

 into thin tufts, issuing without visible order, ovate in circumference, with scarcely 

 distinguishable main axis; fig. o. When grown to the length of 2 — 3 mm., these 

 already bear ripe antheridia or sporocarpia in various stages of development, from 

 recently etablished un til almost ripe; fig. 4 — 5. Certain tetrasporangic branch-systems 

 or stånds of tetrasporangia resemble the stånds of antheridia and sporocarpia, and carry 

 ripe tetrasporangia, even when only abont 2 mm. long; fig. 6. Others are longer, less 

 metamorphosed, with certain axes sterile, growing and branching, while the other side- 

 axes bear a few tetrasporangia. I do not know for certain, which is the ultimate fäte of these 

 metamorphosed branch-systems thrown out by the autumn plant for the development 

 of the organs of reproduction; but I have reason to believe that they are dissolved or 

 fall off, when their functions are accomplished. However, one finds now and then, although 

 rarely, at the end of spring or the commencement of summer, specimens that differ in 

 habit from the common spring plants by those portions, which have persisted through 

 the winter, bearing bushy, long- and richly branched, not distinctly racemose branch- 

 systems, whose axes throughout their whole length are beset Avith thinly scattered, 

 very short, blunt, sometimes slightly club-shaped processes. These seem to point to 

 these branch-systems being stånds of sporocarpia grown out, possibly such whose car- 



