542 



Karl A. Grönwall. 



solid rock before a height is reached of 210 metres above the sea, 

 from which we have one of a white, crystalline limestone {N:o 110), 

 a rock which agrees perfectly with that previously described {N:o 

 112), and evidently of the same origin as the latter. 



In his diary-notes Dr. Wegener states: "Bei 210 m. beginnt 

 eine grosse Schutthalde, welche roten und grünen Sandstein verhüllt, 

 und fast ganz aus Bruchstücken des Gipfelkalkes besteht (nach der 

 grünlichen Farbe)", — There are two specimens of this red "sand- 

 stone", both procured as talus boulders, one (N:o 130) at 210 metres 

 above the sea, the other (N:o 132) at 100 metres. On closer examin- 

 ation, this rock 



proves, how- 

 ever, to be, not 

 a sandstone but 

 a limestone. It 

 is extremely 

 finely crystal- 

 line, and, on 

 weathering, the 

 rock gives the 

 impression of 

 being a fine- 

 grained sand- 

 stone. Diluted 



hydrochloric 

 acid dissolves 

 the rock com- 

 pletely, leaving 

 an unimportant 

 residuum of 

 reddish quartz- 

 grains. Both pieces are red, with white spots, and have a mottled 

 surface. From specimen 132, the surface of which is somewhat 

 weathered, it is seen that these white calcareous parts are definitely 

 outlined remains of some organic origin (the case is probably the 

 same with N:o 130, but I have not been able to decide the matter 

 with certainty, as I did not consider it right to sacrifice any of the 

 little fragment at my disposal to make a thin section). These tube- 

 shaped calcareous formations are about 1 mm. thick, have a wind- 

 ing, irregular course and sometimes have ramifications. In some 

 of the specimens one can see on the surface that they are hollow, 

 so that their form can be called cylindrical. 



A thin section of these formations (Fig. 8—9) shows, on micro - 



Fig. 8. Slide of the red limestone, containing quartz- 

 grains from the Cape Jungersen section, specimen N:o 

 132. Enlarged 3 diam. This thin section shows the 

 irregular shape and extension of the tubes, 

 considered to be "algæ". 



