179 



Casts of Äucella Pallasii. are fairly abundant in a light- 

 coloured sandstone which crops out in Aucella River in the 

 south-west of Jameson's Land. The fossils agree exactly with 

 Lahdsen's description and also with the figures. The largest 

 specimen (a cast) is 43'"°i in length. 



According to Lahdsen, Aucella Pallasii is an excellent 

 guide-fossil for the lowest Virgatus-beds in the lower Volga- 

 stage, w^hich A. P. Pavlow places in the Middle Portlandian ^). 



Aucella Pallasii is quoted from the Kimeridge Clay of 

 Lincolnshire-). It has also been found by Nathorst^) in the 

 dark-grey, marly, bituminous limestone of Nordenskiölds Berg 

 in the Svenska Forlandet and in boulders of a black carbona- 

 ceous shale from Tordenskjolds Berg in Kung Karls Ö (King 

 Karl's Land). 



Myoconcha Sowerby. 

 Myoconcha grönlandica. nov. sp. 



PI. VI, figs. 8 and 9. 



Two fairly well-preserved casts in coarse brown sandstone 

 of a species of Myoconcha have been obtained from Mount 

 Nathorst. The larger one, the posterior end of \\hich is wanting, 

 must have been about ЮЗ^^^^ in length; the breadth is 29™"^ 

 and the thickness 23°^"". The smaller specimen, in which the 

 posterior end is also lacking, must have been about 85"™ long; 

 the breadth is 26"" and the thickness 15"". The shape of 

 these casts, and especially the fact that they have a deep 

 depression corresponding to the position of the ridge on the 

 posterior border of the muscular impression, show clearly that 



') Pavlow, A. P. 1901. Comparaison du Portlandien de Russie avec celui 

 de Boulonnais. Compte-rendu du VllI. Congrès géologique inter- 

 national 1900. Paris. 



'') Woodward, H. В. 1895, p. 371. 



') PoMPECKJ, J. F. 1899. Marines Mesozoicum von König-Karls-Land. 

 Öfvers. Vetenskaps-Akademiens Förh. Stockholm. No. 5, p. 457 — 8. 



12^ 



