KONGL. SV. VET. AKADEMIENS HANDL. BAND. 19. NK) 6. 69 



5. Platyceras enorme n. 



?1. 11 figs 59—72. 



Theea anceps 1859. Fii. Schmidt (nee Puillips) Guologie der luscl (jollaiid, Archiv Naturk. Estlands Bd II, 442. 

 Theca sp. 1867. Lindstuom Nomina, 23. 



Shell straight, cylindrical, with a diminutive spire of one and a half whorls. Many 

 specimens are curved as a crescent or a bow. The last whorl is considerably develo- 

 ped and large and the spire has dwindled to a mere appendage to it. In its general 

 shape the shell thus resembles a diminutive Lituite. The surface is covered by trans- 

 verse, sinuous striae, the edges of which in the best preserved specimens project as thin 

 reflcxed lamella; witli smaller ones between them. PL II f. 72. These are intersected 

 by line, longitudinal lines, interrupted by the transverse ones as seen in fig. 71. The 

 aperture, tigs G6, 67, is oval or circular with thin lips, often sinuous or wavy. Length 

 17 millim., diameter at the aperture 8 millim. From the shale at Djupvik in Eksta^ 

 Rikvide in Nar, in the sandstone of Bursvik, in the oolitic beds of Hafdhem, Nils and 

 Bursvik, and in the limestone beds at Hammar in Kriiklingbo, Klinteberg and Lanna 

 near Slite, from which last locality the Mineral Cabinet of the University of Upsala has 

 obtained specimens, collected by Professor P. T. Cleve. 



This species and the following belong to that group of the Platycerata, which 

 J. Hall has called Orthonychia and which is so prevalent both in the Devonian and 

 the Carboniferous limestone strata. 



6. Platyceras cyatMnum n. 



PI. VII fig. 22. 



Shell conical, nearly straight without spii'c of whorls, rapidly increasing in width, 

 spirally twisted in two bends. Surface concentrically striated by line transverse lines 

 of growth and wrinkled in the same direction. Aperture circular with thin edges. 

 Shell thick, consisting of several strata, glossy, opaque with only faint traces of prisms. 



Length of the single specimen found 80 millim., breadth of aperture 20 millim., 

 at the apex 2 millim. 



Only one specimen has hitherto been found in the Crinoidal limestone of Fol- 



lingbo. 



This species is related to the Bohemian Capulus anguinus Bakuande and kindred. 



Fam. V. BELLEROPHONTID^ Mac Coy. 



Sliell globular or discoid, symmetrical or slightly deviating from the discoid plan, 

 aperture loidened icith an angular slit in its dorsal or superior edge, forming by conti- 



