141 DR G. W. LEE ON 



various publications that the so-called "Mountain Limestone" of Spitsbergen, Beeren 

 Eiland, Nowaja Semlja, etc., really belongs to the upper divisions of the system, and 

 was identified as Mountain Limestone owing to the fact that the older palaeontologists 

 did not realise the importance of a closer comparison with the marine phases of the 

 Upper Paleozoic formations.* 



As regards former records of Carboniferous rocks in Nowaja Semlja, very little need 

 be said here. Professor Tschernyschew has ably summarised in his great work (loc. 

 cit., pp. 679-681) all the data bearing on this question, the main facts being as follows: — 

 According to him, the numerous species described by Professor Toula from the Barents 

 [sland,t and generally believed to be Upper Carboniferous, belong to beds of Artinsk 

 age ; the other Carboniferous fossils recorded from various parts of the two main islands 

 are too scanty to permit of determining their true horizons. However, a few fossils 

 collected during the expedition of the lermak in 1901 (Kreuz Bay and Maschigin 

 Bay) indicate a horizon which is not more recent than the Middle Carboniferous 

 of the Urals. 



These circumstances explain the absence of any reference by me in the descriptions 

 below to species previously recorded from Nowaja Semlja, careful comparison having 

 shown that this fauna is more closely related to that of the typical Lower Carboniferous 

 districts of Russia and Western Europe. On the other hand, a region of which so little 

 is known might have been the seat of the persistence of older types, or of the early 

 appearance of forms known elsewhere from higher horizons only, so that in the determina- 

 tions I have avoided confining myself to literature dealing exclusively with Lower 

 Carboniferous palaeontology. 



Before passing to the descriptive part of this paper, I wish to thank Dr Bruce for 

 having kindly allowed me to study his valuable collection ; and I owe a debt of gratitude 

 to Professor Th. Tschernyschew, who generously furnished me with valuable information 

 touching the geology of Arctic Russia. For help of a varied nature I must express my 

 indebtedness to many of my colleagues, specially to Mr R. Lunn, who sacrificed much of 

 his time in the preparation of the accompanying plates. 



Figs. 42, 43, 44, 46, 47, 48, and 50« are from drawings by Mr H. S. M'Vey, and 

 figs. 12a, 13d, 15a, 17a, 22-22d, 246, 34a, 35, 36, 37a, and 49 are from drawings 

 by myself. 



Descriptive Part. 



As the main object of the following descriptions is to bring out the faunistic and 

 stratigraphical relations of the species, I have not dwelt at length on morphological 

 features unless these have appeared to me to be new or of importance in systematics. 



* Frkch, Lethxa Geognostica (passim) ; J. G. Andeksson, Uber die Stiatigraphie und TeJctonik der Baren Insel, 

 1899, p. 16 ; Th. Tschernyschew, " Die obercarbonischen Bracbiopoden des Ural und des Timan," Mem. Com. Gdol. 

 Russie, 1902, p. 694. 



t Sitzungsb. k Ahad. Wiss. IVien, Bd. Ixxi., 1. Abth., 1875. 



