twexhofel: expedition to the Baltic provinces. 321 



On the coast south of Hapsal, near the village Pasko, are extensive 

 exposures of a white crystalline limestone. The outcrops are on the 

 beach, and the rock appears to have been formed from an old coral 

 reef. Well-preserved coral masses strew the beach and have con- 

 tributed a great deal of material to the many stone walls of the ad- 

 joining lands. These are the most fossiliferous exposures of this 

 division that were seen. The corals consist of Favosites, Heliolitidae, 

 Halysites, Clathrodictyon, Syringophyllum, Acervularia and several 

 species of horn corals. 



Other localities where the Raikiill beds are exposed are IVIexhoff, 

 Piometz, Endama, Allenkiill, Teknal, Wieso, Wodja, Tenja, and the 

 island Kassar to the south of Dago. 



Besides the corals mentioned as being present in the Raikiill beds, 

 there are the trilobites Encrinurus pnnctatus, lUacnus livonicus Holm, 

 Phacops elcgans Sars and Boeck, Proetus planedorsatus; the bryozoans 

 Vinciilaria megastoma Eichwald and V. nodulosa Eichwald. Brachio- 

 pods appear to be quite rare. At Raikiill and Wahlokiill Schmidt 

 states the occurrence of the graptolite Diplograptus estonus Schmidt ^ 

 and at the latter place Deiplwn forbesi Barrande. 



Addifer formation. This formation was designated by Schmidt 

 the Pentamerus estonus beds by reason of the great numbers of that 

 brachiopod which are commonly present. The section exposed in the 

 ciuarry at Addifer, the estate of Herr E. von Wahl, is taken as the 



type. 



The outcrops of the Addifer formation begin about twenty miles 

 west of Lake Peipus near Pedja Brook and reach the sea south of 

 Hapsal. It has not been identified on the islands, but may underlie 

 the extreme southern end of Dago, and probably does underlie Soela 

 Sound between the islands of Dago and Oesel. The thickness of the 

 formation has never been accurately determined, but it appears that 

 not more than fifty feet are present. 



The formation is separated from that underlying, chiefly on the 

 basis of the introduction of Pentamerus estonus Eichwald, Atrypa 

 reticidaris (Linne) and Eospirifcr radiatus (Sowerby). So far as 

 known, its stratigraphic relations to the Raikiill beds and St. Johannis 

 formation are those of conformability. 



The designation, Pentamerus estonus beds, does not carry the idea 

 that the rocks are largely composed of the shells of one species, as is 

 the case in the P. horealis beds. In this formation the pentamerids 



1 Mem. Acad. imp. sci. St. Pelersb., ser. 7, 30, no. 1, p. 44. 



