The marine Carboniferous of North-east Greenl. and its Brachiopod Fauna. 537 



the microscope the silicification is distinctly visible, and both the 

 chalcedbn — usually of a somewhat yellowish-red colour in the 

 transformed shell parts — and the new-formed colourless quartz, 

 can be observed very clearly. Fig. 5 shows a thin section of this 

 rock. 



There have been obtained some pieces of Chaetetes radians 

 Fisch. {N:o 100) from a height of 60 metres above the sea-level, 

 entirely altered into dolomite, but otherwise extraordinarily well pre- 

 served. In colour they are of a yellowish-white, and the fragments 

 of rock to which they were attached are a dense, light gray-red 

 rock, which does not re-act on the addition of hydrochloric acid 

 and, consequently, is probably entirely altered into dolomite. 



At two higher levels there occur highly recrystallized limestones, 

 dolomitic in a high degree, but still retaining some of the original 

 calcareous matter. Neither contain fossils. At a height of 75 — 80 

 metres there occurred, in a bed 5 metres thick, a very hard, almost 

 black or dark gray rock, which effervesced but feebly on the 

 addition of hydrochloric acid {N:o lOA) and thus forming a fairly pure 

 crystalline dolomite. Somewhat higher, at 85 m. above the sea, 

 there was a closely allied rock {N:o 116); it was yellowish-gray in 

 colour and fairly loose in texture, finely crystalline and, on a super- 

 ficial examination, resembled a sandstone. On the addition of hydro- 

 chloric acid, effervescence ensued, and so it possibly still contains 

 some carbonate of lime. In the rock there were some gliding-sur- 

 faces with a black coating which at once attracts the attention. 



At a level of 90 metres above the sea there occur other rocks 

 viz., partly, a shaly bituminous, almost black limestone (N:o 119), 

 containing rather numerous fossil fragments, especially crinoid stem- 

 joints and brachiopod spines, which are specially prominent on 

 weathered rock surfaces, that acquire a greenish-gray tinge and, 

 secondly, a somewhat crystalline dark gray limestone (N:o 125) which, 

 with some amount of certainty, may be stated to alternate with the 

 more shaly rocks. This bituminous shale agrees very well in ha- 

 bitus with similar rocks on the north side of Hekla Sound, both in 

 Koch's section and in the Conglomerate section. The specimen 

 brought home from this locality in Ingolfs Fjord has not given any 

 fossil allowing of a closer comparison between these rocks in Ingolfs 

 Fjord, while, of the fossils found in the more compacl rock (N:o 125), 

 it has only been possible to determine Prodiictiis lonyispiniis Sow. 



Wegener's diary gives the following information respecting the 

 rocks lying at a higher level and above this bituminous limestone: 



"Schiefer ohne Foss. 105 m. 



"Sehr bröckliger Sandstein, den grünen Lehm liefernd, ohne 



