The marine Carboniferous of North-east Greenl. and its Brachiopod Fauna. 565 



Figs. 9, 10 and 11, while some great difFerence exists between it and 

 the adult specimens he has figured ; these have, especially, the ven- 

 tral valve more strongly arched, and the sinus deeper. 



This species has its principal occurrence in the Sub-Carbonifer- 

 ous deposits, but it also occurs, although very rarelj', in the Urals, 

 in the Schwagerina level, and in India, in the lower part of the 

 Productus limestone. These forms, too, present some slight differ- 

 ences from the typical Sub-Carboniferous form ; thus Tschernyschew 

 states that his form from the Urals has the sinus somewhat narrower, 

 and Waagen states that the form from the Salt Range has a flatter 

 ventral valve than the European forms. 



Our specimen agrees more closely with the form from the upper 

 Carboniferous beds, especially the Indian, while Tschernyschew's 

 figure, which shows an older specimen of about 75 mm. in width 

 presents some difference, especially that the sinus is somewhat nar- 

 rower. The figure of Sp. striatus that agrees most nearly with our 

 specimen, is Waagen's Fig. 5 b, PI. XLIV, which, however, shows a 

 very young specimen of 18 mm. width. 



It is possible that one could unite these forms of Sp. striatus 

 from the Urals, the Salt Range and North-east Greenland, which 

 occur in younger deposits, as a variety of Sp. striatus Mart., as they 

 really agree very closely with each other. 



N:o 7. Spirifer supramosquensis Nik. 



PI. XXVII, Figs. 14—16. 



For synonyms see Tschernyschew, 1902, p. 155; Wiman, 1914, 

 p. 47. 



This species is the brachiopod form that is most numerously 

 represented in the Lower Marine group in North-east Greenland. Of 

 this species, 7 specimens have been obtained from the Mallemuk- 

 fjæld — 4 of them under N:o 190, and 1 each under N:os 192, 152 

 and 157. The six first-named were found in the solid rock of bitu- 

 minous, marly limestone, and represent only the ventral valve. The 

 last (N:o 157) was found free-lying and is inbedded in the fine-grained 

 reddish limestone, which is so common in the Lower Marine group. 

 This specimen has both valves preserved, but is so greatly com- 

 pressed that, unfortunately, it does not give any reliable information. 



No fully reliable specimen of this species occurs from the loca- 

 lities on Amdrup's Land, but a little piece of the umbonal part of 

 the ventral valve of a Spirifer {N:o 161) can scarcely belong to any 

 other species. 



The species belonging to the Sp. mosquensis group are so closely 



