16 LIXXARSSON, BRACHIOPODA OF THE PARADOXIDES BEDS. 



kulle and Lovened in Westrogothia, at Andrarum in Scania, and 

 in tlie isle of Bornholm. Also in the arenaceous ilagstones which 

 in the island of Oland contain Paradoxides Tessini similar forms 

 are found. 



Obolus (?) sp. indet. 



Pl. III, fig. 81. 



Because of its general shape, I refer to the genus Obohis a 

 species of which the materials are verv unsatisfactory, so that 1 

 will not create for it a specific name. though it is easily distin- 

 guished from all the Primordial Brachiopoda of Sweden. The best 

 specimen is an interiör (fig. 31), somewhat mutilated anteriorlv, 

 and with the innermost shell layers partly exfoliated. Its Avidth 

 is 16 mm., the length about 14 mm. The shell is very sllghtly 

 convex; its circumference resembles a sector of a circle ; the front 

 is broadly rounded; the slopes forming the beak seem to be 

 nearlv straight, and make a somewhat obtuse angle. The sur- 

 face is not well preserved in any specimen; judglng, however, from 

 some small fragments, I should think that a concentric striation 

 is prevailing, but that there are also radiating ribs. In the inner 

 shell layers little more than a longitudinal striation is seen; the 

 innermost are perforated by small punctiform pits. The inner 

 layers are polished and glossy, the outermost seems to be opaque. 



Of this species I have only found a few, mostly very frag- 

 mentary specimens at Lill viken in the province of Jemtland, in 

 loose masses of bituminous limestone, belonging to the strata 

 with Paradoxides Forchliammeri. They were associated with 

 Orthis Lindströmi, Ovtltis e.vporrecta and Äcrothele coriacea. The 

 species is, in its general shape, not unlike Obolus phimbeus Salt., 

 which is, however, distingulshed by having the surface polished 

 and marked with very distinct radiating striaj. The latter also 

 occurs at a much higher horizon. 



Acrotreta socialis v. Seebach. 



Pl. III, figs. 32-35. 



Acrotreta socialis v. Seebach, Zeitschr. der Dcutschen geol. Ge- 

 sellschaft, vol. XVII, 1865, p. 341, pl. VIII a, figs. 1—4. 



Shell small, nearly circular in circumference, but somewhat 

 truncated posteriorly. Ventral valve acutely conic-al, with the 



