30 T. G. HALLE, LOWER DEVONIAN PLANTS FROM RÖRAGEN IN NORWAY. 



tudinal furrows. Five of these furrows are visible in the exposed half of the capsule: 

 their total number is probably 12 on the whole circumference. Tlie furrows appear to 

 be a little different, some being a little less deep and broad than the others. The two 

 kinds of furrows alternate with each other, the exposed half of the capsule showing 3 

 broader and 2 narrower furrows. The upper part of the capsule is somewhat damaged, 

 a hollow being worn out in some manner a little obliquely to the apex; the apex, however, 

 appears to be rounded. The capsule is only little flattened: its diameter perpendicular 

 to the bedding of the rock is two-thirds of that parallel to the bedding plane. This is 

 shown by a comparison of fig. 24 with fig. 25, which is a photograph in the same magni- 

 fication taken from the side, after the capsule had been removed from the matrix. 



The specimen now described not only retains its original shape better than any of 

 the others, but its inner structure, too, is partially preserved. This is due to petrifica- 

 tion by means of some reddish brown ferruginous substance. It was possible to remove 

 the capsule from the matrix, though the lower end was broken off in the process. The 

 specimen was handed över to Mr. A. R. Andersson of the Geological Institution at 

 Upsala who succeeded in the difficult task of preparing a longitudinal section of it. The 

 cohesion leaves much to be desired because of the imperfect state of the petrification, and 

 the section had to be kept rather thick. It is very difficult, therefore, to obtain photo- 

 graphs which show anything of the structure, although this can be fairly well seen in 

 strong illumination. The photographs in pl. 3, figs. 26 — 32, however, give some idea 

 of the general plan of structure. Fig. 26 is a photograph in low magnification of the 

 whole of the capsule with the exception of the broken basal part. In the lower fourth 

 part of the section, the structure is seen to be uniform throughout. In the median zone 

 there can be seen (not in the photograph) remains of rectangular cells elongated in the 

 direction of the axis. In the upper three-fourths of the section there is a more pronounced 

 differentiation. At the periphery there is a fairly distinct wall about 0,20— 0,30 mm. 

 thick. This wall is best seen in figs. 28 and 29, in which there can be observed remains 

 of the rectangular cells drawn out in the direction of the axis. The wall is evidently 

 composed of several layers of cells, how many it is impossible to decide. In the apical 

 dome-shaped portion, the outer part of the wall is developed in a peculiar manner, 

 appearing as a dense reddish brown band in the section. 



Inside the wall there is a zone, about 0,8 mm. broad, which presents a very peculiar 

 aspect. It is clark coloured, as seen in surface illumination, but is perforated by numerous 

 holes. These are sometimes confluent, causing wider perforations of irregular outlines, 

 but when seen single they are round, with a diameter of about 0,o-2o mm. on an average. 

 These holes are caused by the spores which ha ve fallen out during the process of grinding 

 down the section. The denser mäss in which these holes occur is very dark, but in strong 

 illumination it is found to be composed of spores cemented by some kind of brown sub- 

 stance whether this be of organic or ferruginous nature. The diameter of the spores and 

 of the holes appears to vary somewhat, but this evidently depends on how they have 

 been cut by the section. The perforated aspect of the sporiferous zone is more or less 

 distinctly shown by all the microphotographs in figs. 26 — 29, pl. 3. The spores them- 

 selves are shown in figs. 30 — 32. 



