Ig. 
» 
ig. 13. 
14. 
10. 
16. 
rg 
18. 
19. 
SoS Sp Ge So os 
= 
KONGL. SV. VET. AKADEMIENS HANDLINGAR. BAND. 20. N:0 5. 
Vertical, tangential thin section. 1°/). 
Part of the basal system of the frond in thin radial section. 7), 
Part of the thickening system of the frond. 4°), 
Part of horizontal, tangential, superficial thin section. 7°°/,. 
Section of a part of the frond provided with a conceptacle of sporangia. an ee 
Part of the roof of a conceptacle of sporangia, delivered from lime. 7"), 
. ] 400 
Sporangium, fy. 
PLATE 6. 
Lithothamnion flavescens. /%y. 1~7. 
Part of frond covering Lithothamion compactum. !/,. 
Conceptacle of sporangia, seen from above. 4°/,. 
Thin radial section with a grown-in conceptacle of sporangia. Of the sporangia only the 
j . i 40 
tips remain. I 
Thin radical section of the lower part of the frond. 4), 
Part of horizontal, tangentical, superficial thin section. 79),. 
Part of the roof of a conceptacle of sporangia, delivered from lime. 4°"), 
Lithothamnion compactum. Ivy. S—12. 
Part of a crust-complex with a young crust on its surface. '/). 
Thin vertical section of an older crust-complex. 7°). 
Part of the basal system of the frond in thin radial section. 4/,. 
Part of the thickening system of the frond. 4°), 
Part of snperficial, horizontal, tangential thin section. 4°/). 
PLATE 7. 
Rhodomela virgata. 
First year’s plant in summer habit. !/,. 
First year’s plant in autumnal habit. 1). 
Part of a branch with stands of sporocarps developed during the winter. ! 
Stand of sporocarps. 4°/,. 
Stand of antheridia. 7°/,. 
Stand of tetrasporangia, 4°/!. 
Part of cross section of the main axis of an older plant near the base. %”)). 
Part of median longitudinal section of the main axis of an older plant near the base. *° 
PLATE 8. 
Rhodomela subfusca. 
First year's plant in summer- and autumn-habit.  !/ 
First year's plant in winter habit. 1/). 
1 
gelinated 
