SAMUEL WENDELL WILLISTON 681 
tology as long as he was in New Haven. This led to the renewal 
of his medical studies. 
While acting as assistant in paleontology he studied medicine 
at Yale, received the degree of M.D. in 1880, continued his post- 
graduate studies, and received the degree of Ph.D. at Yale in 1885. 
He then became demonstrator of anatomy (1885-86) and professor 
of anatomy (1886-90) at Yale and practiced medicine in New 
Haven, where he was health officer in 1888-90. 
In 1886 he published some criticisms of Koken’s work on 
Ornithocheirus hilsensis which give us some hint of his abiding 
interest in Kansas fossil reptiles, an interest which was soon to 
bring great results. 
The turning-point in his scientific career, from anatomy and 
medicine to paleontology, came at the age of thirty-eight, when 
he returned to the University of Kansas as professor of geology. 
Kansas was the scene of his first inspiration in paleontology, and 
here his fossil studies and vigorous health marked the happiest 
period of his life. He taught both vertebrate and invertebrate 
paleontology, anatomy, and medicine, and several of his students 
have achieved distinction in these fields.t With respect to the 
breadth of his studies and of his influence at this time, his life was 
comparable only to that of Joseph Leidy, who, it will be recalled, 
was at once an anatomist, a physician, a paleontologist, and a 
microscopist of distinction. He soon began to publish studies on 
the Cretaceous reptiles of Kansas. Henceforth Kansas plesiosaurs 
and turtles, mosasaurs and pterodactyls, were the subjects of a long 
list of papers, mostly in the Kansas University Quarterly, from 
1890 to 1899, with occasional articles on Kansas fossil mammals 
(Platygonus, Aceratherium, Teleoceras fossiger). Meanwhile he 
made many explorations of the Cretaceous of Kansas for fossil 
reptiles. At Kansas University Williston also kept up his two 
avocations of anatomy and dipterology; he served as professor of 
anatomy and dean of the medical school. He also continued to 
publish many papers on recent Diptera. 
t Among these paleontologic students, who have since become known for their 
researches, were: E. C. Case, C. E. McClung, Roy L. Moodie, Herman Douthitt, 
Alban Stewart, Elmer S. Riggs, Barnum Brown, M. G. Mehl, and E. H. Sellards. 
