164 Macfarlane on the Primitive Formations 



and Senjen, where the preponderating rock is mica schist ; with 

 which limestone, more or less granular, is very generally inter- 

 stratified. Besides these, more or less characteristic gneiss, horn- 

 blende, chlorite, and talc schist occur as subordinate constituents. 

 Well-defined clay slate is of comparatively rare occurrence, aj- 

 though the mica schist often assumes an argillaceous character. 



The second region is that spread out to a considerable distance, 

 in the directions before mentioned, around Trondhjem. In this also 

 the mica schist may be termed the preponderating rock, but the 

 jnterstratified limestone is less frequent. Moreover clay slate and 

 chloritic schist are of far greater frequency than in the first named 

 district, as is also serpentine ; which latter rock may be said to be 

 characteristic of the second district, especially of that part of it 

 which constitutes the Dovrefjeld Mountains. The serpentine 

 masses seem to be irregularly in terst ratified with the slates, and 

 sometimes to graduate into them. The greenstones and granites, 

 besides occurring in distinct beds, often form irregular masses and 

 regular veins, intersecting the schistose members of the group. 

 Here, as in the two groups of rocks already described in this 

 paper, these crystalline rocks, as they approach their limits, gra- 

 dually assume a schistose structure. Not only does " the green- 

 stone, in this way, change into hornblende slate or greenstone 

 slate, and the granite become gneissoid, but the greenstone is 

 found even to graduate into mica schist and clay slate. The more 

 purely granular the greenstones are, the more does the form of 

 the deposit deviate from that of a layer or bed. 



Various subdivisions or zones have been distinguished in this 

 group, which greatly difi"er in their general strike. The principal 

 zone of the Dovre^eld Mountains, seems to run E.N.E., which is 

 also about the direction of the Dovre^eld range. The dip 

 varies much, but seems to be, on an average, about 45'^. To judge 

 from the direction of the dips given on the geological map, vari- 

 ous folds occur in the strata, from their junction with the primi- 

 tive gneiss, to where they graduate into fossiliferous beds. 



In the country south of Trondhjem, the mountain masses of 

 Dovrefjeld and Fillefjeld, consist principally of the micaceous, ar- 

 gillaceous, and chloritic schists, already referred to. They con- 

 stitute ns it were, the pedestal for the higher peaks of these 

 ranges, such as the Jotunfjeld. These peaks are generally of 

 igneous rocks. The Faastenen are, however, composed of serpen- 

 tine, and Snehsetten, of a peculiar sort of gneiss. 



