54 FOSSIL MEDLTS.E. 



The piece was washed out ou tbe shore of Ontika, in Esthonia; was found at the 

 foot of the Glint, and donated to the Reval provincial museum by Barou Hermaun 

 Toll-Kuckers. Judging by the rock, it belougs evidently to the sandy layers inter- 

 calated in the upper blue clay, in which the Cruzianas and Fraeuas of the Eophyton 

 sandstone were also found. Further finds may be expected.' 



I fully agree with Mr. Matthew, that the original name given by Torell, 

 costata, should be retained for this species. 



Medusina princeps Torell (sp.). 

 PI. XXVIII, fig. 1. 



Protolyellia princeps Torell, 1870. Lunds Universitets Arks-Skrift, 1869, No. VIII, 



p. 10. 

 Astylospongia radiata Linnarsson (ex parte?), 1871. Kongl. svensk. Vet.-Akad. 



Handl., vol. 9, No. 7, p. 13, PI. II, fig. 15. 

 Medimtes favosus Nathorst, 1881. Kongl. svensk. Vet.-Akad. Handl., vol. 19, No. 1, 



p. 25, PI. V, figs. 5 and 6? 

 Medusites princeps Matthew, 1890. Trans. Royal Soc. Canada, Vol. VIII, Sec. IV, 



p. 140. 



The original description is as follows: 



Orbicularis, pileo fungi similis, niargine distincto; superficies superior convexa 

 interdum impressione media, calcibus nullis iusigni; inferior plauo-couvexa medio 

 pedunculo brevi affixa et calcybus polygonis obliquis complauatis, ut iu A Iveolite. 



Diam. calycum, l-2 mm ; diam. speciminis maximi, 72 mm ; crassitudo, 20"" u . 



Locus: In saxo formationis cambric;e ad Luginls, Vestrogothia?. 



In the remarks following the description the species is compared with 

 Archseocyathus Billings, to show that it has no affinities with it or the 

 sponges, and that its relations are with the genera Lyellia and Alveolites of 

 the corals. 



Dr. Nathorst points out the differences between Dr. Torell's species, 

 P. princeps and M. radiata, and describes the former as a new species, 

 Medusites favosus, as follows: 



A species probably belonging to the acraspedote medusae, family Cyaueidse, 

 with circular gastric cavity, whose roof (or bottom), bounded by the umbrella, is 

 divided into irregularly polygonal fields by small furrows. Diameter of gastric 

 cavity generally about 35-40""", though specimens are found both smaller and twice 

 as large. 



Dr. Nathorst says (in a footnote) that the specific name princeps can 

 hardly be retained, considering the present view of the nature of the fossil. 



1 Meni. Acad. imp. sci. St. Petersbourg, 7th series, Vol. XXXVI, No. 2, 1888, p. 27. 



