26 ANNUAL REPORT OF THE 



REPORT ON THE DEPARTMENT OF VERTEBRATE 



PALAEONTOLOGY. 



By Ciiakles R. Eastman. 



An extended collecting trip undertaken by the Assistant during 

 the late summer and fall of 1900, resulted in substantial benefit to 

 the Department. A number of very excellent Triassic fishes were 

 secured from the vicinity of Boon ton, New Jersey, where excava- 

 tions for a reservoir had opened up a large area of fossiliferous 

 strata. An account of this locality, with illustrations of the lead- 

 ing species of Semionotus there occurring, appeared in a recent 

 number of a popular magazine. In the same way, advantage was 

 taken of the operations for reducing the grade along the Union 

 Pacific Railroad west of Green River, and elsewhere in Wy- 

 oming, to obtain a representative suite of Green River (Eocene) 

 fishes. The work of the Assistant being unfortunately interrupted 

 at this point, arrangements have been made for resuming the field 

 during the present season in co-operation with several western 

 geologists and collectors. Among the more interesting specimens 

 obtained by purchase, should be mentioned a perfect example each 

 of Lepidosteas simplex Leidy, and Xiphotrygon acutidens Cope 

 (Heliobatis radians Marsh), from the Green River Eocene of Fossil, 

 Wyoming ; also a. skull of the interesting Chelydroid, Toxochelys 

 latiremus Cope, from the Niobrara Cretaceous of western Kansas. 

 A fine skeleton of Hesperornis from the Kansan Cretaceous was 

 offered to the Museum for purchase, but not upon such terms 

 that it could be accepted. No additions of consequence have been 

 made to the Mammalian series during the year. A visit was made 

 by Professor H. F. Osborn during the spring for the purpose 

 of studying the collection of fossil Titanotheres. 



