KONGL. SV. VET. AKADEMIENS HANDL. BAND. 19. N:0 6. 101 



Divisio II. ORISP^. 



12. Pleurotomaria Lloydii Soweeby. 



Pl. VII fig. 43—49, pl. VIII lig. 1. 



Plewolomaria Lloydii 1839 Sow. in Sil. Syst. II, 619, pl. 8 f. 14. 



1843 Morris Catal. Brit. Foss. 1 Ed., 158. 

 Murchisonia Lloydii 1841 Akcuiac & Verneuil Bull. Soc. Geol., 160. 



1848 Bronn Nomenclator, 748. 



1850 D'Okbignv Piodrome I, 31. 



1854 Morris Catiil., 259. 



1855 Mac Coy Palajozoic Fossils, 293. 

 1867 Salteu Silm-ia, 532. 



Shell turbinated, whorls six or seven, veutricose. The slit band is situated exactly 

 on the middle line of the body whorl and a little below the upper suture of the other 

 whorls. It is broad, elevated, witli an even surface and, as far as can be made out 

 from the not quite complete specimens, covered with distantiated crescents and smooth 

 interspaces. Above the slit band there are some twelve longitudinal ridges of equal 

 size and parallel to them smaller, threadfine lines, both crossed by fine, distantiated 

 transverse lines. Bencath the slit band the longitudinal ridges are not so numerous, 

 four at the highest and much unequal. Near the suture the transverse lines are thicker 

 than higher up. The apex of the shell has been filled up with solid, calcareous matter 

 and the lowest whorl of the nucleus ends consequently in a blunt point. The aper- 

 ture is large and obliquely ovate (Pl. VII f. 43). The umbilicus is narrow and open. 



Widely spread as this shell is, it seems to be much variable and there are many 

 Gotland specimens, which only hesitatingly and provisionally can be refered to Pl. 

 Lloydii, as the English species according to the figure given by Sowerby is more elon- 

 gated and the whorls by far not so ventricose as in the former. Mac Coy 1. c. also 

 says that he has not seen specimens of the same length as in Sowerby's figure. His 

 descriptions nearly agree with the Swedish specimens. 



The variety from the shale beds near Wisby (Pl. VII figs 46 — 49) has still more 

 ventricose whorls and the parts around the slit band not so much angularly prominent 

 as in those from the other localities and it may rank as a well distinct variety. 



Next, there is a depressed, short form, chiefly found as nuclei with indistinct 

 impi-essions of sculpture and with the body whorl nearly elliptical in a longitudinal 

 section. A few specimens of this, concerning which it for the present cannot be de- 

 cided, whether it is a variety or an independent species, has been found at Wester- 

 garn, in Östergarn at Gannviken and Grogarn, and in Ardre. Its dimensions are:height 

 32 millim., breadth 31 mm. apical angle 87°. 



The typical specimens of Pl. Lloydii attain a height of 49 millim., breadth of 

 34 mill., apical angle 56 °. 



It has chiefly been found in the shale beds at Wisby, Follingbo, Westergarn, 

 Djupvik in Eksta, Habblingbo, Alfva saw mill, Qvinnegårda in Hafdhem, the canal from 



