ZOOLOGICAL DISTRIBUTION OF DISEASE. 259 
joint ends of bones. Rheumatic gout, or, as it is now 
more appropriately termed, osteo-arthritis, is a disease 
of great interest, for it has a wide zoological distribution, 
-and has even been detected in the joints of the extinct 
Irish Elk (Wegaceros hibernicus). This disease is cha- 
racterized by enlargement of the ends of bone, destruc- 
tion of the cartilage and synovial membrane of joints, 
with calcification of the ligaments. It is no respecter of 
persons; young and old, rich and poor, high and low, 
suffer from it. I have detected the disease in the joints 
of a snake’s backbone, in birds of various kinds, including 
the neck of an ostrich, in cats, dogs, leopards, lions, 
tigers, horses especially, oxen, sheep, kangaroos, bears, 
and many others. It is as far as I can ascertain the 
mest widely diffused of all the bone diseases to which 
vertebrated animals are liable. 
In order to show the care necessary in such generali- 
zations we may take the recent additions to our know- 
ledge of such a long recognized disease as cretinism. 
All visitors to Switzerland, the Rhone and Aosta valleys, 
are familiar with what is termed endemic goitre and 
endemic cretinism. The leading features of cretinism 
are briefly these :—The disease is congenital, and dis- 
plays itself in unnatural shortness of the trunk and 
limbs, malformations of the skull (as a rule it is unusually 
small), and idiocy, combined with abnormal conditions 
of the thyroid body. Cretins, as those affected with 
this disease are called, present a characteristic appear- 
ance ; a typical cretin is represented in fig. 126, taken 
from the admirable report, compiled by a Commission, 
created by the King of Sardinia, to inquire into this 
