1909.] RECENT BIOLOGY OF SOME LIVING SHELLS. 749 



the island of Oeland, afterwards in 1867 withdrew the statement, 

 and in the first part of his ' Bidi-ag til Kundskaben om Norges 

 Arktiske Fauna,' ji. 92, he says : '■'■ Derimod er den ikke Jios os 

 forefundeii fossil i vor glaciale Formation, idef Angivelserne om 

 deits Forekomst her, som mins Fader senere har oplyst, gritnde 

 sig paa en For^vexling med den i Form og Storelse meget lignende 

 Lutraria elliptica Lamarck^ 



De Geer overlooked this correction when he cited Sars as an 

 authority for the occurrence of the shell in shell-beds at Trondhjem. 

 Gwyn Jeffreys was similarly misled when he claimed that it occurs 

 in the beds of the "glacial formation" at Ohristiania 50-200 feet 

 above the sea-level, quoting Sars, 'ISTorges geologiskeUndersogelse.' 



It is true that in a posthumous MS. work of Professor Minister 

 he quotes the shell from a shell-bed at Smedholm, near Brevik, 

 bvit inasmuch as this bed is only '66 m. above the water-level, it 

 would seem from the observations of Oyen at the neighbouring 

 place called Davo, where the conditions are similar, that at 

 Smedholm the Mya arenaria has recently been washed up by the 

 tide and been mixed with shells from the other shell-beds. Brdgger 

 similarly explains the finding of the shell at the level of the sea at 

 Yallo, where again it does not occur in the raised shell-beds, no 

 more than it does in those in the shell-beds at Storeng, Tromo and 

 Arendal [oj). cit. pp. 606-607) ; so that it is clear that it does not 

 occur in any of the true raised beaches of the Ohristianiafiord or 

 the Langesundfiord, oi- in anyplace on those fiords where there is 

 any evidence that the land has changed its level since its arrival. 

 On this Brogger and his colleagues are quite agreed. 



There only remains one other place in Norway where 3It/a 

 arenaria has been stated to occur in a raised beach, and to which 

 Professor Brogger attaches more importance. This is at Kadland, 

 at the south-west point of Norway. 



In a notice by H. Rasch of a journey he made thither in 1833, 

 he mentions going from Mandal along the river to Kadland. He 

 found on the western bank of the river, where it rises in a kind of 

 precipice 24 feet high, that the upper 16 feet of this was a coarse 

 sand containing no remains, under which lay a bed of vegetable 

 leaves, etc., matted together, i7iter alia hazel, birch, aspen, etc. 

 This bed was sharply defined above and below ; the lowest 5 feet 

 consisted of a bed of '' leerblandet " sand, in the upper part of 

 which were a few scattered shells, and in the lower, shells in 

 great numbers, consisting of the ordinary mollusca living on the 

 coast, ex. gr. Ostrea edulis, Venus islandica, exoleta and Ulterata, 

 Mya arenaria, truncata and arctica, Buccinum reticulatum and 

 capillus, T-urbo littoralis, Trochus cinereus, Turritella terehra and 

 edule. The river at this point was a rapid one. (Mag. f . Natur- 

 vidensk. etc. 1836, pp. 299 & 300.) 



Keilhau, who visited the place in 1838, confirmed the descrip- 

 tion of Rasch, giving more details. He reported further that 

 he had been told that when the tide in the sea was high there 

 was a large indraft of salt-water vip this river, so that it became 



