( 699 ) 
ist. In Malmö near Christiania which is not very important 
to us; 
20d, In Gothland, where Scumipt describes its occurrence as follows : 
“Das grosse Centralmergelgebiet von Follingbo bis Slite und Farö, 
das bald aus reinen Mergeln, bald aus Mergeln mit Kalken wech- 
selnd besteht, wird neben andern Fossilien besonders durch die 
urspriingliche Leperditia baltica His. mit kammförmiger Zeichnung 
wif dem Umsehlag der linken Schale characterisirt, die einerseits 
auch bis zu den Mergeln von Westergarn vordringt und andererseits 
sich vielfach auch in den oberen Kalken der Wisby-Region findet, 
so bei Heideby und Martebo. Auf F rö bei Lansa kommt sie zusam- 
men mit Zaphrentis conulus Lanpstr., Strophomena imbrea VERN. u. a. 
im Kalk vor, weehselnd mit Megalomus-banken.” (20, p. 255). These 
places belong to Scumipt’s middle zone; besides KorMopin records it 
from Oestergarn and Hammarudd near Kräklingbo (8, p. 134), where 
no doubt younger strata are found. In these two places I have 
been seeking for a long time, but failed to find it. According to 
LanpsrröM : b—e. 
3, In Oesel this species is a type-fossil of the Lower Oesel- 
zone I. For a long time it was only known from dolomite from 
Kiddemetz (var. Lichwaldi) but has later also been found in lime- 
stones in the peninsula of Taggamois on the N. W. coast, thus 
verifying Scumipr’s prediction. Only there this zone consists of erys- 
talline limestone ; everywhere else of dolomite or marl (9, p. 46—49). 
With regard to the origin of these boulders whose age has now 
been determined, the following remarks may be stated. First of all 
the fact that Skine cannot be thought of, as Leperditia baltica does 
not occur there. In general the marly character of the rock found 
in Gothland, argues against the possibility of its originating there ; no 
doubt we have only to think of the north eastern part of the island. 
Though indeed our boulders do not make the least impression of 
originating in marly strata, it does not say so very much, because 
in Gothland the limestome with ZL. baltica cannot everywhere be 
decidedly looked upon as being limestone from marl. The question 
then about their origin is not to be solved without extensive material 
for comparison, which I do not possess; only a single piece of lime- 
stone from Slite does not correspond with our boulders. Tis lime- 
stone from Slite is differently coloured and also much more crystalline 
and betrays by marl-remains and a small coneretion of little pyrite- 
crystals its origin from marl. Now as regards Oesel, from this region, 
too, I have but a single piece with ZL. baltica for comparison. It is 
from Kiro, immediately to the south of Taggamois, and corresponds 
48 
Proceedings Royal Acad. Amsterdam. Vol. VIL. 
