On Jurassic and Cretaceous fossils from Nortli-Kast Greenland. 479 



IVoni pari of the \eiilial margin lorming a semicircle; the posterior 

 part of the circumference very Hke the half part of an ellipse. The 

 shell strongly arched in the neighhourhood of the posterior margin, 

 otherwise rallier Hat. No sinus on the palliai line. The hinge not 

 observed. 



Height of the cast 28 mm, its length '.M\ mm and thickness (of a 

 single valve) ca. 7 mm. 



To judge from the right valves the available casts agree very 

 well with Roiillier's above-cited figure. 



Distribution. North- East Greenland: "Kløft 1" on Store 

 Koldewey Island (1 spec). At "4. Sænkning" also on Store Koldewey 

 Island (1 spec). — On the toj) of Muschelberg, Hochstetter's Foreland 

 (2 spec). 



Russia: at Kharoschowo. 



00. Cyprina Syssollae Kkyskhlin(i. 

 PI. XXXV. fig. 6. 



184(). Cfiprina Si/ssollae Keyserling, I'etschora-Land, p. a09; PI. 17. figs. 17- 22. 



The shell rounded-triangular, relatively higher and shorter than 

 in the previous sjjecies, fairly tlat. The umbo somewhat in front of 

 the middle, rather prominent. — The front part of the cardinal 

 margin more concave than in the preл'ious species. Lunula not 

 sharply marked olf. The surface covered with coarse and fine, 

 concentric striae. 



All the available specimens (casts and imprints) are more or 

 less defective; their form has been partly somewhat altered by pres- 

 sure. The following measurements can be given of an imprint of a 

 right valve somewhat deformed in this way: 



Height 25 mm, length 29 mm and thickness ca. 9 mm. 



Distribution. North-East Greenland: "Kløft Г' on Store 

 Koldewey Island (many spec). At "4. Sænkning" on the same 

 island (5 spec). — Top of Muschelberg on Hochstetter's Foreland 

 (1 .spec). 



Russia: in deposits with Belenmites Pdiideriamis. 



01. Cyprina cfr. inconspicua Lixdstkom. 



1865. Cyprina inconspicua Lindström, Trias- och Juraförsteningar från Spetsbergen. 



p. 11; PI. 3, figs. 7—8. 



A cast of a left valve and a second specimen with the greater 

 part of the shell preserved have a great resemblance to this species, 

 but yet diiïer so much from it, that they must perhaps be referred 

 to another species. 



