Skånes Colonusskift'er 



55 



we have several reasons for rejecting the name »Cardiola shale » (in the sense of 

 Tullberg). We are namely now knowiug that Cardiola interrupta Sow. also is to 

 be met with in somewhat older strata; it e. g. has been collected by Törnquist in 

 the Retiolites-bearing shales of Dalarna. In Thuringia, it is even noted as charac- 

 teristic of the »Cardiola-limestone» or »Ockerkalk», which according to Eisel, is the 

 very equivalent to the Cyrtograptus shale. A great deal deposits, counted as Car- 

 diola shale, have been referred to this only for the reason of Cardiola interrupta 

 Sow. meeting therein, and, besides, if we only are considering the informations 

 now given, it often is impossible to find any reason why the respective deposits 

 have been classified as Cardiola shale or as Coloiius shale. Under such circum- 

 stances it cannot be avoided that, although our researches are directed exclusively 

 upon the Colonus shale, they must be extended to include also all Scanian graptolite 

 shales containing Cardiola interrupta Sow. whatever their age may be. 



As to the horizontal distribution, it is ought to be noted, as mentioned before, 

 that real Colonus shale in Sweden is hitherto with certainty only known from Skåne. 

 A statement by Maek that it should occur at Kinnekulle in Västergötland is, accor- 

 ding to Holm, surely due to a mistake. And Schmalensee's assertion that he has 

 found Monograptus colonus Barr, (i. e. Colonus shale) at Stygforsen in Dalarna is, 

 as Törnquist remarks, not to consider as fully reliable. In 1910 Munthe men- 

 tions the find of Monograptus colonus Barr, in marl shale from Southern Gottland, 

 but it may well be a matter of doubt whether that shale can be considered as a de- 

 velopment of real Colonus shale. 



The sketch map (pag. 8) shows the area within which the Colonus shale is 

 to be found; the more remarkable points in this area are signed by figures, indi- 

 cated in the complete list of localities mentioned in the literature (pag. 7 — 10). The 

 foresaid area, as can be seen from the sketch map, occupies a belt running from S E. 

 towards the N W., beginning in the district of Simrishamn and ending at Tågarp 

 in the neighbourhood of Landskrona. This belt has a breadth of about 15 km. and 

 a length of 100 km. If only Colonus shales were met with in the whole of the 

 designed area, its square size should be calculated to 1500 □-km. Högbom assigns 

 it to be 1200 □-km., but also this value is surely too high. For reasons, appea- 

 ring from the preceding, it is impossible at present to point out the exact extent, 



The harder rocks of the complex are greatly distributed as boulders in the 

 moraines of Southern Skåne. Tullberg already accentuates the lithological and 

 faunistic agreement between knobs of Scanian colonus-bearing limestones and some 

 morainic boulders known of from Northern Germany as »Graptolithengestein». 



The thickness of the Colonus shale is certainly very considerable. Tullberg 

 tells us that it is 1128 m. at least. To such a result he surely has reached only 

 by calculating the thickness under the supposition that the dip of the strata was 

 constant in the whole district of the complex. In reality, the total thickness cannot 

 be, even approximately, given, already from the reason that the overlying strata are 

 nowhere known ; not to speak of the case that over- and underlying strata never 



