Bulletin of the Museum of Comparative Zoology 

 AT HARVARD COLLEGE. 



Vol. LVI. No. 3. 



\ 



GEOLOGICAL SERIES, Vol. X. SHALER MEMORIAL SERIES, No. 2. 



EXPEDITION TO THE BALTIC PROVINCES OF RUSSIA 



AND SCANDINAVIA. 



PART 1.— THE CORRELATION OF THE ORDOVICIAN STRATA 



OF THE BALTIC BASIN WITH THOSE OF EASTERN 



NORTH A:^IERICA. 



By Percy E. Raymond. 



With Eight Plates. 



CAMBRIDGE, MASS., U. S. A. 



PRINTED FOR THE MUSEUM. 



July, 1916. 



