Willi ston.] The Upper Cretaceous. 31 



mon, which furnished to the world the discovery of the then 

 startling fact of birds with genuine teeth. Under the date of 

 September 2 of that year, Professor Marsh wrote to him in- 

 quiring about his summer collections in the Cretaceous, with 

 the offer to "determine any reptilian or bird remains without 

 expense," and stating that he would give him " full credit" for 

 their discovery. Under date of September 25 he again wrote 

 to him, acknowledging the receipt of a box of fossils, and stating 

 that the "hollow bones are part of a bird, and the two jaws be- 

 long to a small saurian. The latter is peculiar, and I wish I had 

 some of the vertebras for comparison with other Kansas species." 

 The latter is the Colonosaurus mudgei Marsh, which was after- 

 Avards found to belong with the bird specimen. 



In the autumn of 1872, Marsh, with a small party, made 

 another expedition into the same region. These were the only 

 times that Marsh personally visited these regions, all of his col- 

 lections being afterward obtained by parties employed by him. 



In 1873 Mudge again spent some time in the exploration of the 

 ( retaceous beds in the more northern part of the state — the 

 only region that was at all safe from marauding Indians. 



In 1874 Professor Mudge began systematic collections for 

 Yale College, assisted by Mr. Henry Turner, of Clay Center. In 

 July of that year his party was joined by Mr. (now Doctor) 

 Harry A. Brous, of Manhattan, and myself, and explorations 

 were continued into November along the Saline and Smoky 

 Hill rivers. 



In 1875 explorations for Yale College were eontinued by Pro- 

 fessor Mudge, assisted by Mr. Brous and myself, from March 

 to October. 



In 1876 the party under charge of Professor Mudge consisted 

 of Mr. Brous, Mr. E. W. Guild, who had been collecting the 

 previous year independently, for Yale, Mr. G. P. Cooper, of To- 

 peka, and myself. Work was continued until late in November. 



In 1877 the party (under charge of myself ) collecting for Yale 

 College consisted of Mr. Guild, Mr. Cooper, and my brother, 

 Mr. F. H. Williston. 



Meanwhile Mr. Charles Sternberg had collected by himself in 



