330 bulletin: museum of comparative zoology. 



4. Syringopora reticulata Hisinger. 



5. Whitfieldella didyma. 



6. prunum. 



7. Rhipidomella hybrida. 



8. Murchisonia cingulata Hisinger. 



9. Platyschisma helicites (Sowerby). 



10. Pleurotomaria undata Sowerby. 



11. Holopella obsoleta Sowerby. 



12. Ilionia prisca (Hisinger). 



13. Pterinea retroflexa Wahlenberg. 



14. Orthoceras imbricatum Wahlenberg. 



15. Leperditia baltica. 



16. Encrinurus? obtusus Angelin. 



17. Eurypterus fischeri Eichwaldi. 



The exposures northwest of Arensburg and on the west coast are 

 rarely extensive, consisting of small quarries in the interior and a few 

 low cliffs on the coast. 



Padel, about nine miles from Arensburg and on the road to Rotzikiill, 

 has an exposure of fully four feet of very finely crystalline limestone 

 which in fresh exposures is probably thick-bedded, but under the 

 action of sun and frost the rock separates into thin slabs. The fauna 

 is the same as that at Sagaristi, and Whitfieldella didyma is the most 

 common fossil. About a mile west of Padel is the Koggul quarry. 

 The elevation is in the neighborhood of ten feet higher and the beds 

 may be a little higher stratigraphically, but there is no certainty re- 

 garding this point. About ten feet of thick-bedded, chocolate colored 

 limestone are exposed. Fossils are not abvmdant; but large omphalo- 

 trochoid gastropods and small Whitfieldella didyma are not uncommon. 

 Other fossils from here are Crotallocrinus rugosus Miller, Avicidopecten 

 danbyi (McCoy), Goniophora cymbaeformis Sowerby, Megalomus 

 gothlandicus Lindstrom, and Encrinurus pundatus. A form closely 

 related to Eospirifer radiatus also occurs at this locality. Another 

 small quarry at Limadau exposes about two feet of very hard compact 

 limestone containing hardly any fossils. 



Rotzikiill is the noted eurypterid locality, made famous through 

 the labors of Schmidt, Holm, and others, and which has long been the 

 European Mecca for students of this group of organisms. The eury- 

 pterid layer is well exposed in a small cjuarry on the shore to the south 

 of the village and the base of the quarry is from six to eight feet above 

 sea-level. At the base are eighteen inches of white fine-grained 



