On Jurassic and Cretaceous fossils from North-East Greenland. 47Л 



Loose-lying stones liom "4, Sænkning" contain a numl)er of speci- 

 mens, np to 9 mm high, of an Astarte with creniilated margin; these 

 may also he referred probably to the present species. 



Distribution. North- East (ireenland: "Kløfl I" on Store 

 Koldewey Island (5 spec); "4. Sænkning" on the same Island (many 

 spec). 



Russia: black sand at Mniowniki. 



(i er m any: Brauner Jura s in Wurthemberg. 



England: Great Oolite. 



40. Astarte alta n. sp. 

 PI. XXXIV. tig. 2. 



The shell comparatively high and short, moderately arched, 

 triangular-ovoid. The umbo median, pointed and very projecting, 

 and bent somewhat forwards. The posterior margin slightly convex, 

 passing rather abruptly into the strongly curved ventral margin ; 

 the anterior margin slightly concave. Erom the umbo down to the 

 posterior part of the ventral margin a slightly concave depression. 

 Lunula distinctly marked ofïV The surface covered Avith numerous, 

 somewhat irregular, rather sharp, concentric ribs. The luargin of 

 the shell crenulated. 



Height 13-5 mm, lenght 12 mm and thickness (of a single valve) 

 Ô mm. 



This species is distinguished from A. striato-costata Mü, by its 

 high form and stronger ribs on the younger parts of the shell. 



Distribution. North- East Greenland. "Kløft I" on Store 

 Koldewey Island (1 spec). 



41. "Astarte" retrotracta Rouilliei^. 



1847—48. Astarte retrotracta Rouillikr, Études progr. Géol. Moscou; II étude, p. 414; 



PI. G. fig. 29. 



The valve small, oval, strongly arched. The umbo behind the 

 middle of the valve, inclined somewhat forward; in front of it a 

 distinct, oval lunula. 



The shell itself is only in part preserved in the single available 

 speciiuen ; it seems to have been thin ; its surface has only had 

 finer and coarser concentric striae. The hinge cannot be seen for 

 examination. 



Height 9 mm, length llô mm and thickness (of the cast of a 

 left valve) ca. 3'5 mm. 



Although the hinge is not known in the only specimen and the 

 margin of Ihe shell seems to be smooth, the resemblance otherwise 



