187 



here only fragmentary pieces which are quite impossible to deter- 

 mine, though perhaps identic with L. fruticulosum f. flexuosa, L. 

 tophifomie or L. coralloicles, or species which are most nearly 

 related to these. At least in some places the so-called „skjælsand", 

 e. g. sand mixed with fragments of shells, also comprehends frag- 

 ments of Lithothamnia. 



In banks of shells below the bog postenously the town Bodo 

 in Nordland occur numerous Lithothamnia some feet above the 

 level of the sea. At least some of these must be referred to L. 

 fruticulosum f. typica (and perhaps also f. fastigiata), much re- 

 sembling specimens of the latter which often are found washed 

 ashore and rubbed by the waves. Cp. pl. 23, fig. 1 — 9. 



In sinking a well at Hero in Helgeland Stud. med. Kristian 

 Schreiner had the opportunity to see Lithothamnia from deeper 

 layers. He kindly informed me, that the specimens apparently 

 belonged to the same series of forms as the last named. 



At Garten, a small island at the mouth of the Trondhjem 

 Fjord, I met with similar plants under the green turf just above 

 high-water mark. Pl. 23, fig. 10 — 15. Also these appear to be- 

 tong to L. fruticulosum, sometimes encompassing small stones 

 (fig. 12, 15) sometimes not. At the same place I saw numerous 

 dead specimens at or below lo w- water mark, but I had not occa- 

 sion to ascertain whether they had been east up from deeper 

 water (it seemed to be rather steep below), or perhaps washed 

 out from the bank. 



Thus it appears, that the Lithothamnia also with us and espe- 

 cially along the northern part of the coast have been and still are 

 of essential importance in forming new strata of the earth-crust, 

 ■but the extent of these strata is not yet well known. 



