148 G. LINDSTKOM, ON THK SILUIUAN GASTEOPODA AND VTEROPODA OF GOTLAND. 



Several specimens have been obtained from Klinteberg unci Sanisugn, and also 

 from Kyrkberget in Wisby. 



It reminds, as to the ornamentation, of Troehus Gotlandicns, but the transverse 

 striie arc more straight in that species and sigmoid in Tr. Stuxbergi, moreover the 

 umbilical side and the shape of the Avhorls is quite different in both. 



5. Troclius undulans n. 



PI. XVI tig. 8—10. 



Shell small, obtusely conical of five tumid whorls, bulging out near their inferior 

 part and with the sides above straight and vertical, whence the body whorl actpiires 

 a cup shaped appearance or also they arc of a concave outline, fig. 8. The oblique, 

 transverse lamellte of growth are distantiated, and have their projecting edges much 

 wavy and folded in a great number of siimosities, quite peculiar to this species. The 

 umbilical side is nearly flat, in the centre excavated into a deep funnel, on the bottom 

 of which the opening of the narrow umbilicus is seen. The horizontal ridge wiiicli 

 all around borders tiiis surface is thin and wavy. The aperture is circular, enclosed 

 within thick lips, the outer one being especially large and in its uppermost corner 

 angulated. 



H. 8 mill., br. 12 mill. ^ .>, :,.„^ . 



Only three specimens have been found, two from the upper limestone beds of 

 Slite and the third from Samsugn in Othem. 



6. Troehus profundus n. 



PI. XVI fig. 11 — 13. 



Shell of moderate size, broadly conical with large periphery of tlie umbilical side 

 and short spire. Si.x whorls of somewhat concave contour. The ornamentation con- 

 sists of oblique, transverse striiu or rather steplike gradations following each other at 

 wider distances than the striae in the preceding species. When seen in a section, 

 cutting them transversally they have a serrated appearance. The umbilical side is quite 

 smooth and glossy, excavated or cup-shaped, through the large, very thin, upwards 

 directed borders, which encircle the upper side of the whorls and the aperture. This 

 ,^^ is circular and lies at some distance inside the border of the shell. A 



\)/^ shallow, curved groove in direct continuation with the aperture, indicates 

 ^^ the place the animal occupied when protruding itself froni the shell. 



o7'i>lXi's"nrofin"-" '^^^^ outcr Up is thill and sharp, the interior one thicker and straight. 

 du8, natural size, f]^^, uuibilicus is opcu and wide; the axis is open as seen in the annexed 

 woodcut. H. 13 mm., br. 16 mm. 



Two specimens have been found in the limestone of Samsugn in Othem. In 

 this, as well as in the following species and Tr. Stuxbergi and Tr. undulans, the 



