472 J- P- J- Ravx. 



The shell fairly flat, ovoid to circular with small, pointed, 

 median umho. The anterior margin somewhat concave; the posterior 

 margin straight, passing evenly over into the rather strongly curved 

 ventral margin. The older parts of the shell covered with dense, con- 

 centric folds and with finer concentric striae; the younger parts 

 smoother, with fainter concentric folds and striae. 



Height and length 9 mm. 



The available specimens show such great resemblance to some 

 of the figures given by Ilova'i'sky (especially with fig. 19) of A. de- 

 pressoides Lahus. 1 , that one might be tempted to refer them to this 

 species, or perhaps more correctly to A. levilimbnta Ilova'i'sky, which 

 is only distinguished from the former by having a smooth margin 

 and can thus probably not be separated from it. On the other hand, 

 they differ considerably in form from Lahusen's figures of this spe- 

 cies 2 , to which therefore I have not ventured to refer them. 



Distribution. North-East Greenland: "Kloft I" on Store 

 Koldewey Island (3 spec). 



Russia: in the zone with Aspidoceras biarmatum (Oxfordian). 



Germany: Upper Dogger. 



39. Astarte minima PHILLIPS. 



(18291 1835. Astarte minima Phillips, Geology of Yorkshire, I; PI. 9, fig. 23. 



1853. Astarte minima Phillips; Morris and Lycett, Mollusca from the Great Oolite. 



II, p. 82; PI. 9, fig. 10. 

 1858. — — ; Quenstedt, Der Jura, p. 444; PI. 61, fig. 4. 



1861. — — — ; Trautschold, Recherches geologiques etc., p. 82; 



PI. 7, fig. 6. 



The shell strongly rounded-triangular, almost circular, fairly Hat. 

 The beak but little prominent. The surface covered with 10 — 12 

 rather coarse, concentric folds; the folds nearest the umbo the strongest; 

 the younger part of the shell almost perfectly smooth. 



Height ca. 3 mm ; length a little more. 



The available specimens from "Kloft I" agree well in form with 

 the specimen figured by Trautschold from the black sand at 

 Mniowniki, but seem to differ therefrom in the fact, that the folds 

 are lost down towards the ventral margin. From English and German 

 specimens they are distinguished by their less triangular form. 

 Possibly they should rather be regarded as young specimens of 

 .4. depressa Quenst. (Der Jura, p. 505; PI. 67, figs. 29—34) from 

 "Brauner Jura t"; in this species, namely, the younger parts of the 

 shell may also be smooth as in the Greenland specimens. 



1 Ilova'i'sky: L'Oxfordien et le Sequanien etc., p. 256; PI. 9, figs. 12—22. 

 - Lahusex: Jurass. Bild. des Rjasanschen Gouv., PI. 2, tig. 27. 



