76 G. LlNDöTKÖM, ON THli ÖJI.UK1AN (;ASTK(.U'UDA AN]) TTEliOroDA OJj' GOTLAND. 



joiii the slit band at aii luiglo of 38°; tliey beiul outvvards towards tlie sides and again 

 converge towards the uinbiliciis. The slit band forms an elevated keel vvith a flat top, 

 on each side bordered by a fino line and wavy with the niinute and delicate liues of 

 growth. Whorls foiir and a half, regularly inci'easing in width, twice as large as high 

 and eonsequently not so narrow as in Bell. sphiura. Shell thick and as conimon in 

 this genus, at thickest aroiiiid the umbilicus and at the inferior eorners of the aper- 

 ture. The last Avhorl, when seen from the side, is straight or only faintly curved, and 

 its apertural and dorsal contours are nearly parallel, f. 26. In my specimens, whieh 

 are not quite complete, the aperture is longer than the rest of the shell. The infe- 

 rior eorners of the aperture near the umbilicus, where the shell is at thickest, are 

 rounded or cylindrical and completely hide the umbilicus, which in young specimens 

 is open. Diamet. 20 millims., breadth at the fragmentary aperture 17 millims., height 

 of the aperture 7 millim. 



Occurs in the shale beds of Eksta at Djupvik and in Fröjel. It is nearly related 

 to Bell. spha^ra, but difiers by haviiig the umbilicus entirely covered by a fold of the 

 reflexed börder of the a[)erture. The shell is moreover thicker and the direction of 

 the transverse stria; and their angle when joining the slit band quite different. 



4. Belleroplion tsenia n. 



Pl. VI figs. 22—25, pl. VII %s. 4—5. 



Shell discoid Avith six much compressed and thin whorls, transverse, nearly el- 

 liptical in their section, twice as broad as high, their dorsal side only a little convex» 

 in many nearly flat, the lateral angles very thin and acute. All whorls are visible 

 on the umbilical as well as on the apical side. The only specimen which shows 

 some fragments of the expanded aperture makes it not clear whether there has 

 been an open or closed umbilicus, but it seems likely that it has been more narrow 

 than may be judged of by its wideness in the other samples. At the aperture, which 

 seems to have been quite as large as in Bell. sphajra, the shell attains its greatest 

 thickness and consists of several strata. On other parts, where fragments of it still 

 are seen, it is very thin. The transverse stria3 of the surface are nearly straight or 

 only faintl)' curved in an angle of 68° near the slit band. This band is narrow and 

 only a little elevated betAveen two sharpedged lines. Height 60 millim., breadth of 

 aperture 60 millim., breadth of the last whorl near the aperture 28 millim., height 19 

 inillim. Occurs in the lower limestone beds at Östergarn and Ardre, and also on 

 the shore of Hammar in Kräklingbo, and in the soft gray limestone of Lindeklint and Fröjel. 



5. Belleroplion fastigiatus n. 



Pl. VI, iigs. 1—10. 



Shell rather more discoid than globular, aperture transverse and triangulär in outline, 

 the base being only sliglitly arched. It is incomplete, the margins brokeu off and 



