S06 Geology of Scandinavia. 



of Jurassic formation which M. Hisinger, in his excellent geo- 

 logical map of southern Sweden, represents in the southern 

 part of the island of Gottland. This is one of the most norther- 

 ly points in which this formation has as yet been shewn to oc- 

 cur. M. Hisinger, in his work entitled LcBthea suecica, men- 

 tions, as occurring in the island of Gottland, fossils which prove 

 indisputably that the lias occurs there, as, for instance, the 

 Gryphoea arctiata the Lima gigantea, and the vertebrae of 

 Ichthiosauri. It would be interesting to possess a collection of 

 the fossils of this deposit, in order to compare them with those 

 entombed at the same period in more southern climates. 



I should also recommend to the notice of the naturalists of 

 the expedition, the deposit of coal which occurs in the island of 

 Bornholm, and which one is inclined to refer, like that of Brora 

 in Scotland, to the Jurassic formation. A series of the animal 

 and vegetable fossils by which this combustible is probably ac- 

 companied, would be interesting. 



But, if the tertiary and secondary periods are only repre- 

 sented in the Scandinavian peninsula by patches of inconsider- 

 able extent, we are partly indemnified for this by the great de- 

 velopment of the more ancient deposits which are called transi- 

 tion. The deposits of this period cover whole provinces, and 

 occur most frequently in almost horizontal beds, which are as 

 easily examined as the Jurassic formations of France and England. 

 These formations are filled with numerous and well preserved 

 fossils. It would be interesting to possess originals of the remark- 

 able figures published by M. Hisinger in his Lcethea snecica ; 

 and it would, perhaps, still be more interesting to possess the 

 fossils of the transition-formations of Norway. As yet no special 

 description of these last has been published, not even of those 

 which are contained in the slate and limestone of Christiania.* 

 At Christiania itself, M. de Buch informs me, in going up 

 the Jggers-Elv, towards Aggers-KirJce, we find many ortho- 

 ceratites in this limestone. The alum mine of Opslo includes 

 ellipsoidal globules of limestone, each of which contains a pe- 

 trifaction ; but the greatest number of these organic bodies is 



• In Keilhau's Gaea Norwe^ica there is a valuable memoir on the Trilo- 

 hites of Norway Edit. 



