KONGL. SV. VET. AKADEMIENS HANDLINGAR. BAND 32. N:0 I. 93 



This species is restricted to the higher limits of the stratum d aud also in f in 

 the northern part of the isle of Gotland and has been foimd in the isle of Fårö, at 

 Ryssnäs, Dember, Alnäse and Länsa, and also at Ar and Slite. 



Propora conferta. E. & H. 



Pl. VIII, figs. 32—39; pl. IX, figs. 1—23, 31, 32, 35. 



'? 1819. Madreporites luainmillaris Wahlenberg. Petref. Suec, p. 98. Probablj' the same species, as he gives 



Alleberg as locality, where this is the only Propora. 

 1851. Propora conferta E. & H. Pol. Palaeoz., p. 225. 



1858. » » p. p. Fkiedk. Schmidt. Untersuchung, Archiv, p. 225. 



1860. » » E. & H. H. N. Cor. Ill, p. 242. 



1865. Heliolites affinis BiLLINöS. Canad. Geol. aud Natural., 2 Ser., vol. II, p. 427. 



1866. » » ID. Catal. Foss. of Anticosti, p. 5, 30, fig. 12. 

 1871. Heliolites dubia TÖRXQUIST. Lagerföljdea i Dalarne, p. 19. 



1873. Plasmopora conferta p. p. Ldm. Sv. Undersiluriska koraller. Ofversigt Vet.-Akad. Förhandl. N:r 4, p. 24. 



1873. Plasmopora affinis Ldm. Ibid., p. 25. 



1880. a conferta ID. Fragm. Silnrica, p. 33, Tab. I, f. 6—7. 



1880. » affinis ID. Ibid., p. 33, Tab. I, f. 8—9. 



1882. » i Id. Silur. Korall, aus Russland, p. 13. 



1883. Propora conferta F. KOEMER. Leth. Geogn., I, p. 512. 



1888. Plasmopora conferta Ldm. List. of foss. Fauna Sweden, I, p. 19, 23. 

 1888. » affinis Id. Ibid., 1, p. 23. 



The first authors of this species gave no figures of it and a ver}^ short description 

 and said themselves that it »n'est encore qu'iinparfaitement connue>^ It was therefore of 

 the greatest importance to know the specimens upon which they had founded their species. 

 With the greatest readiness Professor Henei Dodvillé, the distinguished keeper of the 

 museum of »Ecole des Mines» in Paris answered my application to see them and placed 

 them in my hands for examination. These two specimens had been collected by M. 

 E. DE Verneuil during his Voyage in Russia in 1844 together with Sir Rod. Muechison. 

 One is from Borkholm, the other from »Chavli Canal de Windau», but the latter is probably 

 not found in situ as there are no Silurian strata near that place. The accompanying labels 

 in the hand of Jules Haime, as Prof. Douvillé assures, are signed »Propora 2», this 

 number meening the second species of their new genus Propora, which in their works is 

 just this. As I was at liberty to make the necessary sections out of them I could with 

 certainty identify a number of specimens from other localities. I then also found that 

 Heliolites affinis Billings, of which I had received typical specimens from the author, 

 almost entirely coincided in irs structure with the Propora conferta, onlv differing a little 

 as to the size of the calicles etc. That it should be regarded as identical with this species, 

 I hope the sections on plates viii and ix will also sufficiently show. 



It has grown in disciform or sphseroidal masses and has generallj'^ the calicles so 

 closel}^ set, that there is very little place left for any coenenchyma. They attain a diameter 

 of 1,5 millim. or even less in those formeriv called »affinis». They are only slightly exsert 



K. Sv. Vet. Akad. Handl. Band 32. N:o 1. 12 



