368 Ortmann — Invertebrate Fossils from Patagonia. 



Art. XXXYII. — Synopsis of the Collections of Invertebrate 

 fossils made by the Princeton Expedition to Southern 

 Patagonia ; by Dr. A. E. Ortmann. 



In the February number (1900) of this Journal, Mr. J. B. 

 Hatcher has given a general account of the sedimentary rocks 

 of Southern Patagonia, frequently (pp. 98, 101-104, 108) 

 referring to the present writer's studies on the fossils of this 

 region. Since these studies have now come to an end, it seems 

 well to give a preliminary report on the chief results obtained, 

 in order to give an idea of the richness of the material at 

 hand, and to enable the scientific public to get a more correct 

 understanding of the beds in question than has hitherto been 

 possible. A final report on the Tertiary Paleontology of 

 Southern Patagonia will be given by the writer in a volume of 

 the "Princeton Expedition to Patagonia," which is in course 

 of preparation, and will be freely illustrated by figures of all 

 species represented, drawn by Mr. F. van Iterson. It is hoped 

 that this volume will be ready by the end of this year or the 

 beginning of next. 



The present article is intended to treat only of the so-called 

 " Patagonian formation." As Mr. Hatcher has already pointed 

 out (1. c, p. 101), we have sufficient reason to believe, that the 

 different marine horizons distinguished by F. Ameghino and 

 accepted — at least in part — by H. von Ihering (the Patagonian 

 formation, divided into a " Piso Juliense " and "Piso Leo- 

 nense," and Suprapatagonian beds or lower part of the Santa- 

 Cruz-formation) are identical, i. e., belong in one and the same 

 continuous series of marine deposits underlying the Mam- 

 miferous Santa-Cruz-formation, and we retain the old term 

 Patagonian formation for this series, which is certainly a 

 paleontological unit, and belongs, as the writer is now fully 

 satisfied, in the Lower Miocene. The fauna of this series is 

 represented in our collection by over 140 species, many of 

 which are new to science. 



I shall give here first a list of the new species, with short 

 diagnoses and other remarks that are necessary to recognize 

 them, and then I shall add a list of species known from other 

 localities, but not found previously in Patagonia, and shall 

 conclude this article by some remarks on the synonymy ', etc., 

 of known Patagonian forms. 



