428 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1909. 
A visit to the hall of paleontology in the Museum of Natural His- 
tory will enable one to appreciate, by the aid of visible arguments, 
the ideas expounded by Gaudry. It is precisely on these arguments 
(as regards fossil species), taken from all lands, that he has estab- 
lished his doctrine in sober, pure and harmonious language. 
In the last works which we have mentioned Gaudry showed very 
clearly, by the aid of numerous sketches, how the transformist doc- 
trine was the only one which explained the history of fossil animals. 
He succeeded in doing more; he infused into this history a commu- 
nicative enthusiasm, a poetic charm which makes the reading of his 
books as attractive as it is instructive. 
But the scholar was now 75 years old. The official age for retire- 
ment had arrived for him, and it was necessary that he should leave 
his pupils, with whom he had lived in the closest intimacy, and the 
collections which he regarded with a genuine love. The sacrifice was 
so painful that his pupil, M. Boule, who had become in his turn an 
~ eminent master, when called upon to succeed Gaudry, sought to set it 
aside. Gaudry retained his office and all his habits of life, and he 
remained in this hospitable establishment, which he had had so great 
pains to found, until the last day of his life. Until the end he gave 
an astonishing example of continuous labor, lucidity, and productive- 
ness. 
6. The faunas of Patagonia. A part of the Antarctic world. 
From 1904 to 1908 Gaudry directed his researches toward a world 
entirely new to him, to which the discoveries of Ameghino had 
attracted his attention. This world of strange fossil vertebrates of 
Patagonia, so disconcerting to a mind accustomed to European, 
Asiatic, and North American forms, attracted Gaudry. The re- 
markable collections made by the young Frenchman, Tournoiier, of 
the most curious forms of this fauna, supplied him with material 
for new studies, which aroused his enthusiasm, because here again he 
found problems awaiting solution. 
In three successive memoirs he expounded the ideas which his 
studies suggested. A summary of them is as follows: 
Except at the beginning of the Tertiary, the land mammals of Patagonia 
were widely. separated from those of the Northern Hemisphere. All the 
genera were distinct and the majority of them to such a degree that it is not 
possible to place them in the orders established for the mammals of Europe. 
Not alone are the genera different, but the progress of evolution is not the 
same. While the paleontology of our Northern Hemisphere offers us the 
spectacle of a continuous progress, South America shows an arrest of de- 
velopment. In the Miocene, no animal became a ruminant, a pachyderm with 
paired toes, a soliped like a horse, a proboscidian, a placental carnivore, or an 
anthropoid ape. This condition of affairs has continued until the present, 
since mastodons, horses, deer, bears, Machairodi, which have left their 
