230 G. LINDSTRÖM. ON THE SILUUIAN GAISTUOl'0UA AND 1'TKliOPODA OF GOTLAND. 



Plate XII. 



Fig. 1 — 3. Pleurotomaria cirrhosa n., p. 121, specimen from Östergarn, witli details of surface. 



)> 4. Murchisonia cava n., p. 128, from Martebo and details of the slit band. 



1) 5 — 6. » moniliforrnis n., p. 128, from the saudstone of Bursvik. 



» 7. » obtusangula n., p. 128. 



u 8. » subplicata n., p. 129. 



1) 9 — 10. « cingulata His. p. 127, f. 9 the type specimen of Hisingke, which he delineated 



in »Lethrea Suecica» on pl. XI fig. 6 a. In natural size. 



» 11 — 12. Murchisonia obtusangula n., p. 128. 



M 13 — 14. » crispa n., p. 131. 



» 15 — 19. » compressa n., p. 129. Fig. 15, nucleus with traces of sculpture, fig. 17 one 



of the largest nuclei with an obtuse end above the filled up apex, fig. 18 longitudinal 

 section along the median axis, fig. 19 transverse section of the apex, showing the dark 

 apical whorls, filled with organio deposit, and the lighter nucleus of the younger whorls. 



» 20 — 24. Murchisonia attenuata Hisinger p. 130. 



