ICONGL. SV. VET. AKADEMIENS HANDL. BAND. 19. N:o 6. 35 



Turritella cingulata = Murobisonia cingulata p. p. 

 Ttirritella attemtata = Murchisonia attenuata. 

 Pileopsis cornuta 

 Pil. sulcata 



> = Platyceras cornutura. 



There are in reality thus thirteen species described by Hisingeu in tlie Letha3a, 

 when two out of the fourteen are identical with others and one, E. funatus, comprises 

 two different species. Nor has this nuraber been increased in the last publications of 

 HisiNGER, in the sixth part of »Anteckningar» and in »Förteckning öfver en Geognostisk 

 och Petrificat-Samling från Sverige och Norige», printed in 1841. There is, however, 

 the important corrections made that Turitella cingulata is considered to be a Pleuro- 

 tomaria and that Murchisonia compressa is separated from it and referred to separa- 

 tely as "Stenkärnor af Turritellor», Leth. pl. 12, fig. 6 b. 



In »Dia Petrefaktenkunde» by Schlotheim (1820) there is only one of the 

 the Gotland species described on page 162, Trochilites globosus, the type specimen of 

 which I have had occasion to examina through the kindness of Professors Beykich 

 and Dames. It is tha same that somewhat låter was called Euom. funatus by Sowerby. 



Georg Wahlenberg describes in his »Petrificata Telluris Svecana^», published in 



the »Acta Soc. Scient. Upsaliensis (1821), p. 68, Turbinites cornu cuietis, which Sowerby 



had already called Euomphalus discors and further 



Turbinites alatiis Wahl. is = Pleurotomaria alata. 

 Helicitvs catenulatus (p. 72) is = Oriostoma rugosum. 

 Hel. supra Migulatas is identical with 

 Hel. angulatus = Oriostoma angulaturn. 

 Hel. cequilaterus = Pleurot. fequilatera. 



Hel. obvallatus »occuvrit in Gotlandia rarius" = Pleurot. qualteriata p. p. ? 

 Hel. obvallatus Wahlenberg is different from Pl. qualteriata. 



Wahlenberg thus described in all six species, which were låter adopted by 

 Hisinger. 



Professor N. P. Angelin, when a student of the University of Lund, distributed 

 small collections of Gotland fossils under the title: »Museum palasontologicum sveci- 

 cum» and a list of these is printed in the Danish »Naturhistorisk Tidskrift af Kröyer», 

 2* Vol. 1838. Amongst the 50 species there mentioned, we find Euomphalus cornu 

 arietis (— Oriost. discors), but Angelins specimans are Oriostoma Roemeri, Euomphal. 

 alatns His — Pleurot. alata and Littorina? striata n. sp. In the existing copics of the 

 »Museum» no specimens of the last species have been found and consequently the iden- 

 tity cannot be made out- In his Avorks on the Palaaontology of Sweden Angelin has 

 not given any estimate of the numeric value of tha Gastropoda. But he seems to have 

 mentioned as his opinion to Barrande ^) that the Scandinavian Upper Silurian beds 

 were not so rich in these fossils as Bohemia, where Barrande then considered that he 

 had 200 species, a number which is now manifold increased. 



In his paper »On tha Silurian Rocks of Sweden» ^) Sir Roderick Murchison also 

 gave a sketch of the geology of Gotland. On page 29 he enumerates the following 

 nine species of Gastropoda, viz. 



') Paralléle entré les dépöts siluriens de Bohéme et de Soandinavie, p. 59. 

 -) Quarterly Journal, Geol. Society of London 1847, p. 29. 



