KONGL. SV. VET. AKADEMIENS HANDL. BANlJ. 19. N:o 6. 95 



31. Pl. praatexta n. 



32. Pl. togata n. 



33. Pl. frenata n. 



34. Pl. undulans n. 



35. Pl. Marklin! n. 



36. Pl. cirrhosa n. 



VII. PLANORBIFORMES. Shell discoid, slit band sitiiated on the apical side near 

 the suture, narrow, much variable to its sculpture. Schizostoma Bronn p. p. 



37. Pl. planorbis His. 



38. Pl. helicina n. 



VIII. NATIOOIDE.,E. Shell globose, slit band larger than in any other division, at a 

 level with the other surface, ornamentation of the shell of microscopic, oblique 

 lines, also crossing the slit band. Only one species known. 



39. Pl. exquisita n. 



Divisio I. MULTIGARINAT^. 



1. Pleurotomaria scutulata n. 



Pl. VII, figs. 23—25, 28, 29, .30. 



Shell conical, turbinated, whorls eight and a half, globose or rounded, separated 

 from each other through a deep suture, spire acnminate. Slit band situated exactly on 

 the rniddle line of the free body whorl and close to the suture on the superior, visible 

 part of the other whorls. It is narrow, soraewhat concave and with dense, regularl)' 

 curved crescents and one or two faint longitudinal lines crossing thern. The enclosing 

 lines are sharpedged. The slit band is on both sides environed by a belt of different 

 ornamentation than the other surface and this belt is enclosed by one prominent line 

 on each side. Within this area tliere are fine longitudinal and transverse lines cros- 

 sing and above the uppermost line there is also a broad space equally ornamented. This 

 median belt with its central slit band projects as a ridge all around the shell (fig. 25). 

 On each side of the belt there is a longitudinal slight concavity. The ornamentation 

 of the other surface consists of fine cross lines of equal size, forming nodules where 

 they meet and enclosing small squares and rhombs. The aperture is large and nearly 

 ovate. The columellar lip is reflexed and bent a little round the umbilicus, which is 

 large and funnelshaped. 



Height 20 millim., breadth 17 millim. Aperture 11 millim. in height, breadth 9 

 millira. Apical angle 80°. 



This elegant shell occurs in the limestone of Samsugn in Othem, at Stor VVede 

 in Follingbo and at Kyrkberget in Wisby. There is some variability in its shape, with 

 more slender spire (angle 55°) from Follingbo or quite the reverse, 85°, depressed, as 

 those from Samsugn. 



