Prof. Laimorth — Palceozoic Rocks of Britain 8^ Scandinavia. 265 



a. JExstilans Limestone (or subzone of Paradoxides palpebrosiis) , consisting of five or 

 six feet of bituminous limestone, marked by the rich fauna described in 1879 

 by Mr. Linnarsson,' of which the chief forms are: Far adM- ides Tessini, 

 Brongn., P. Hicksii, Salt. (var. palpehrosus) , Linstracus acukatus, Aug., 

 Conocoryphe exsulans, Linn., C. Dalmanni, Kixg. , Agnoshts gibbus, Linnrs.,^. 

 fallax, Linm-s., Acrothele intermedia, Linnrs., Oholdla sagittalis, Salt., and 

 forms of Hyolithus and Lingulella? 



I. Subzone of Paradoxides Eicksii, Salt, (typicalis), consisting of from 12 to 16 

 feet of flaggy beds containing some siu'vivors of the foregoing forms, together 

 with Conocoryphe Dalmanni and Liostracus Linnarssoni. 



c. The terminal subzone consists of schists about ten feet in thickness, in which 

 Paradoxides Tessini is still present, but in which we have no longer evidence 

 of the existence of Paradoxides SicksH. The remaining forms are species of 

 Agnostidte {chiefLj Agnostiifi rex, Barr., A.parvifrons, Linrs., Agnostus fallax, 

 Linrs.), and a form of llicrodiscus. 



3. The next twenty-five feet of strata may be roughly designated as the Zone of 



Paradoxides Davidis, though this species is only doubtfully present in the 

 highest beds. The commonest fossils are Agnostidce. 



4. The Paradoxides- Davidis beds are capped immediately by some two or three 



feet of highly fossiliferous limestone — the well-known " Andrarum Limestone," 

 or Zone of Paradoxides Forchhammeri. In addition to the characteristic species, 

 it contains : — 



Paradoxides Zovem,Ang., Agnostus glandiformis,A.ug., Agnostus brevifrons, 

 Ang., Agnostus aculeatus, Ang., Conocoryphe sp., Selenopleura brachymetopa, 

 Aug., Synlithus tenuistriatus, Linrs., Acrotreta socialis, Seebh., Obolella 

 sagittalis, Salt., Acrothele eoriacea, Linrs., Kutorgina cingulata, Bell, etc, 



5. The terminal zone of the Faradoxidian at this locality is marked by the 



presence of Agnostus l(Bvigatus, Dalm., a form which occm-s also in the under- 

 lying Andrarum Limestone. The beds of this zone are only about five feet in 

 thickness, and are separated from the overlying Olenus -bearing rocks by a bed 

 of Alum schist, about six feet in depth, wholly destitute of organic remains. 



(Olenidian Division). — The Swedish geologists usually break up 

 the fossiliferous strata that intervene between the summit of the 

 Paradoxidian and the basal zone of the Ordovian (or Lower Silurian 

 System) of Sweden into two chief subdivisions — a lower division of 

 Olenus schists and an Upper Division of Dictyonema schists. In 

 Scania the Dictyonema schists are not recognizable as a distinct 

 group ; 2 but they may possibly be represented by the highest 

 Olenus-bearing beds of that region, which occasionally yield frag- 

 ments of Graptolithina, possibly referable to the genus Dictijonema. 

 In any case the Olenus beds and the Dictyonema Schists belong to 

 one and the same systematic rock-gioup, which, like that of the 

 corresponding Welsh Upper Lingula Flags, is easily distinguished 

 palseontologically by its collective fauna from the Paradoxidian 

 below, and the basal beds of the Ordovian above ; and as the genus 

 Olenus is most characteristic, and apparently occurs throughout the 

 entire series, I shall here refer to the collective group as the OlenicUan 

 or Upper Cambrian. 



According to Dr. Lundgren,* the Olenus-bearing strata of Scania 

 contain the following recognizable zones : — 



^ Linnarsson, Fauna af Fxstilans-kaYk., Publications Geol. Siu'vey Sweden, Series 

 3, No. 35, 1879. 



2 Comp. Lapworth, Geological Magazine, 1880. 



3 Linnarsson, Geol. Mag. 1876, p. 42. 



* Lundgren, Ueber Angeliu's geol. Uebersichts-Karte von Schonen, Neuen 

 Jahrbuch fur Mineralogie, etc. 1878. 



