THE COXTINKNTAL FLORA OF SOUTH SWEDEN 265 



of Blekinge to Pataholm, reaches a mean percentage of only 5.6. In its scattered 

 areas further north, as in the parishes of Tuna and Kristdala and in the country to 

 the west and north of Vastervik, the lime-percentage is also rather inconsiderable, 



5-6 %• 



Oland and GoUand. The soil is, of course, almost everywhere strongly calcareous. 



Ilalland. The considerable parts of the province that fall below the uppermost 

 Late-(Hacial marine limit, contain thick layers of marl. On the whole, their lime 

 percentage decreases from north to south. Its mean values are 8.6 — 6 %, but marl 

 with a considerably higher lime-])ercentage is often met with: in the interior parts of 

 the Viska Fjord of former days, for instance, 12 — 14 %. It should be pointed out 

 that these marl-layers are, as a rule, covered by a two feet deep clay, ])oor in lime. 



Vdsiergotland. In the districts south and southwest of the Silurian lime regions (Falbygden) 

 there are moraine deposits (gravel mixed with clay) with a comparatively high i)ercen- 

 tage of lime (15 — 16 °o). In the valleys of the rivers Viskan and Atran there are ice- 

 lake deposits with a pretty high percentage of lime, decreasing towards the south (8 — 

 9 % in the neighbourhood of Ulricehamn, but 4 — 5 °o at Svenljunga; round Boras 

 7 — 15 °o ). The large parts of Vastergotland that fall below the uppermost marine 

 limit are covered by marine clay with a weak lime-percentage; on the great plain 

 south of Lake Vanern the lime-percentage seldom exceeds 2 — 3. 



BohusUin. As in Halland, the marine marl is covered by less calcareous clay. The 

 lime-percentage decreases from south to north (5- — 7 % in the south, but almost 

 limeless clay north of Fjallbacka). — Shell deposits with a high lime-percentage are 

 widespread. 



Dalsland. Calcareous clays are lacking within this province. The calcareous 

 slates in the north-eastern part, however, are of great importance. 



Oslcrgotland. Besides in the Silurian lime district (the Omberg — Roxen — Motala 

 region), there are very calcareous types of soil on the plain south of it (moraine with 

 an average of 17.5 % , os-material with 16.4 % of lime). The plain is bordered on the 

 south by the Archaean rock of Holaveden, which, however, comprises scattered occur- 

 rences of a comparatively calcareous moraine or os-gravel. On the eastern parts of 

 the plain, the country round Linkoping, the only calcareous soil-type is glacial clay, 

 which contains an average of only 5— 6.5 "z, . 



Sodermanland. In the country round Stockholm the lime-percentage in the clays is 

 8 — 10 ?o ; along Lake Malar and in middlemost Sodertorn 4 — 6 °^ ; further south 

 and west it continually decreases. 



Ndrike. In a few minor areas there are remains of Silurian clay- and alum- 

 slates and some limestone. The lime-percentage in the moraine is rather low; the 

 average about 5 "o . Striped clay occurs sporadically, but only at a great depth and 

 with an inconsiderable lime-percentage. 



Vdstmanlaud. The clays in the Valley of Malar are rather poor in lime; in the neigh- 

 bourhood of Sala, 8 — 10 ,%, in the south-eastern part of the province, only 4 — 6 ", ; 

 and to the west it decreases still more. West of the country about Tillberga there is 

 no clay marl. 



Upplatid. In the north-east the lime-percentage in the moraine and the clay is 

 even at small depths very considerable, generally 20 — 30 %. From here it decreases 

 towards the south and south-west. About Upsala it attains an average of 12 — 20 %, 

 but towards the east about Norrtalje it keeps between 8 and i o % . In the southern 

 part of the province the lime-percentage is pretty constantly 10—12. 



