Princeton University, 
E. M. Museum of Archaeology and Geology. 
Princeton, N. J., March i, 1901. 
Sir: 
i 
I have the honor to transmit herewith the Report upon the Tertiary 
Invertebrates collected by the Princeton expeditions to Patagonia, under 
Mr. J. B. Hatcher. 
The collection, being the largest ever made in Patagonia, is valuable 
not only from a palaeontological, but also from a geological and zoogeo- 
graphical point of view, and it has been possible to determine satisfactorily 
the age of these Tertiary beds, and to compare them with other deposits 
of the southern as well as the northern hemisphere. 
This refers especially to what is called, in this report, the Patagonian 
formation, and we may say that we now possess in this marine series a 
standard for correlating any other marine Tertiary beds of the southern 
hemisphere. 
Very respectfully, your obedient servant, 
Arnold E. Ortmann, Ph.D. 
Curator of Invertebrate Pal&ontology. 
Dr. W. B. Scott, 
Professor of Geology , 
Princeton University. 
