64 O. LINDSTUOM, UN THE SILUKIAN GASTROl^ODA AND PTEUOPODA OF GOTLAND. 



? Natica (/laiiciiioides. 

 Natica parva. 



Pilt'opsis vc/.itxtis (? 

 Neiita lialiotiK, 



Capiiius ncritoideii v;iv. xiilcato 

 Natica snhparva. 

 Vapiil.ii.<! fialioh'x. 



Criji ultis eiiomp h a hides. 



Plalt/storiia ningnreiisis (^= e) 

 Ai^rnrtilin haliotis. 



Capulus Branvi. 



Uapidus sidcatus. 



Acroculia cornuta- 

 Acroc. sulcata. 

 Acroculia euomphaloides 

 Naticopsis parva. 



1839. Sow. Sil. Syst., G()3, pi. 3 f. 4. 



1843. Morris Catal. Rrit. Foss. 1st Ed. l.'')4. 



1839. Sow. Sil. Syst. ()12, pi. 5 li<r. 24. 



1843. Morris Catal. 153. 



1848. Bronn Nomencl. 786. 



1848. Phillips Mem. Geol. Survey, II, 259. 



1854. Morris Catal. 2d Ed. 263. 



1854. S.1LTKR in Murcuison Siluria 2(1 Kil , |)l. XXV f. 1. 



vetustatis). 1839. Sow. Sil. Syst. G16. 



1839. Sow. Sil. Syst. 625, pi. 12 f. 16. 



1843. Morris Catal. 154. 



1848. Bronn Nonicncl. 805. 



1862. M.\c Gov Sil. Foss. Ireland, 13. 



1848. Bronn Nomeucl. 217. 



1850. D'Orbigny Prodr. 29. 



1850. Id 1. c. 31. 



1854. Morris Catal. Ed. 2, 239. 



1855. Mac Coy Pal. Foss. 290. 



1857. GiEBKL Zeitschr. f. gesammte Natiirwiss., 165. 



1852. Mac Coy A. N. H. scr. 2. vol. 10, 196. 



1854. Morris Catal. 2d Ed. 239. 



1855. Mac Coy Pal. Foss. 290, pi. 1 K, f. 39. 

 1852. Hall Pal. of N. York vol. II, 287, pi. GO f. 1. 

 1860. F. RoEMER Tennessee, 75, tab. V f. 15. 

 1854. Salter Siluria 2d Ed. 2301 

 1859. Id. Siluria 3d Ed. 548 j ^ '• ^"^ ^- ^■ 

 1871. Baily Figures of cliaract. Brit. Fossils, part. Ill, 64. pi. XXI f. 12. 



1873. Salter Cambridge Fossils, 89, 154. 



1874. Alth Galizien, 31. 

 1857. Giebel Zeitsclir. gesammt. N. W. 167; according to liiin Hisinger's 



Pil. cornuta is the same as Mijnster's Cap. Brauni. Now, even if 

 it could be proved that they were identical, this latter species was 

 created some years later than Hisingers and it would be contrary 

 to all rules of equity and priority to aboli.sli tin; older name. 



1857. Giebel 1. c. 166. 



18G7.1 

 1867./ 



LiNDSTROM Nomina fossiliuin Gotl. 23. 



1873. Salter Cambr. Foss. 171. 

 1873. Id. 1. c. 185. 



Shell of highly variable shape, naticiform with prominent spire, neritoid with 

 depressed spire or planorbiform with sunk spire- Generally transverse or broader than 

 high, with the body whorl enormously developed. The ornamentation of the outside 

 is characteristic. It is very difficult to find specimens, which exhilMt it sufficiently 

 clearly. They have mostly been subjected to the tear and wear on the shore before 

 being imbedded or suffered from corrosion or also been changed after their fossilization. 

 The ornamentation is of the same pattern in all, only changing in minor details. It 

 changes with the age of the shell, different in the young and the adult or on the spire 

 and the last whorls. It consists of two sets of lines, which intersect each other. There 

 are delicate, wavy, longitudinal lines, interrupted by the often irregular lines of growth 

 and other elevated lines. On the spire, pi. II figs. 30—31, the longitudinal lines are 

 threadfine, elevated, with interstices many times surpassing their breadth and at regular 

 distances they are interrupted by the transverse lines. On the body whorl near its 

 middle line the}' have increased in size, Avith minute, microscopical lines between the 

 large transverse ones. On the inferior side the longitudinal lines are large, broad. 



