KONGL. SV. VET. AKADEMIENS HANDLINGAR. BAND. 19. X:0 6. 



159 



following. 



The variety figured pi. XVII f. 4 is in some way a transitional form to the 



2. Oriostoma discors Sow. var. rugosum Sow. 



Delphinula 

 Euomphalus rugosus 



1811. 

 1814. 

 1839. 

 1843. 

 1847. 

 1848. 

 1854. 

 1855. 

 18G7. 

 1871. 

 1873. 

 1814. 

 1818. 

 1828. 

 1829. 

 1831. 

 1831. 

 1837. 

 1840. 

 1858. 

 1867. 

 1876. 

 1883. 



Straparollus rugosus 1850. 

 Stvaparollus catenulatus 1850. 



Euomph. angulosus 

 Helicites catenulatus 



Delphinula catenuluta 



Euomphabis catenulatus 



PI. XVII fig. 5-10. 



Parkinson Org. Rem. Ill, 77, pi. VI f. 7—8. 



Sow. Min. Conch. I, 113, pi. 52 f. 2. 



lu. Sil. Syst., 626, pi. 12 f. 19. 



Morris Catal., 145. 



MuRcuisoN Qu. Jourii. Geol. Soc, 29. 



Bronn Nomenclator, 481. 



Morris Catal. 2d Ed., 248. 



Mac Coy Pal«;oz. Foss., 298. 



Salter Siluiia, Ed. 4, 532, pi. 24 f. 13. 



Baily Charact. Br. Foss. pi. 21 f. 8. 



Salter Catai. Cambr. Foss. 157. 



SowERBY Mill. Conch, vol. I, 114, pi. 52 f. 3. 



Wahlenb. Petref. Suec, 72. 



His. Anteckn. IV, 237. 



Id. Tableau ed. 1, 10. 



Id. Tabl. ed. 2, 8. 



Id. Anteckn. V, 114, tab. 1 fig. a. 



Id. Lethi^a. 37, tab. XI f. 9. 



Id. Forteckn., 55. 



Fr. Schmidt Esthland, 204. 



LiNDSTKo.M Nomina, 23. 



Ferd. Roemer, Leth. Geogn. pi. 14 f. 8. 



Qdenstedt Petrefaktenkunde Deutschlands, le Abth. 7r Bd, 397, pi. 200 f. 90 



(not fig. 91). 

 D'Orb. Prodr. I, 29. 

 Id. Ibid. 30. 



Shell nearly discoidal, spire only a little prominent or turbinated, whorls six, 

 carinated by eight or ten longitudinal keels, interrupted on pretty equal distances by 

 large, sinuous lines of growth, which are elevated in a backwards refiexed fold at the 

 point where they meet the keels, giving in their totality an imbricate or roughly scaly 

 appearance to the surface. Between the larger lines, which are much distantiated, 

 the surface is sculptured by minute lines, parallel with them. The umbilicus is open 

 and the aperture circular with a continuous peristome of thin lips. H. 37 mill., br. 

 68 mill. The lips of the aperture are much unequal, the exterior one being prominent, 

 the interior, deeply insinuated, expecially at its superior corner, the distance between 

 both amounting to 28 milliiu. in one of the largest specimens. It occurs frequently, 

 though not so common as the former, in Faro, at Wialmsudd, Samsugn in Othem, 

 Liinnaberg in Slite, Moner in Boge, Stor Wede in Follingbo, Martebo, Kalens Qvarn 

 and Galgberget near Wisby, in the shale beds of that town, Ostergarn both in the 

 shale and the limestone, Ardre, Bara hill, Liiide, Klinteberg and Frojel. 



The range of variability is very wide within this group. Along with shells of short 

 spire, long spired or turbinate shells occur, and together with those of rare transverse 

 imbrication, there are others which have it dense. The specimens from Ostergarn and 

 Klinteberg are commonly almost disciform, those from Samsugn with long spire and 



