60 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 6l 



Was absent or exceedingly rare in the mountains. 



Was less frequent in the south (Nasca region) than in the north 

 (Chimu). 



The condition showed many variations. The form changes of the 

 head and neck may reach a fairly advanced stage without a trace of 

 inflammation. Of the more affected specimens there were two princi- 

 pal varieties, one characterized by a great shortening of the neck and 

 a pronounced flattening of the head of the femur, with a shallowness 

 and roughness of the acetabulum ; while the other was marked by a 

 deepening of the cotyloid cavity, with less roughness, and the as- 

 sumption by the head of the femur of a shape much resembling the 

 caput penis (see pi. 26). The changes in the acetabulum include in 

 advanced cases the bridging over of the cotyloid notch by irregular 

 masses of bone and a conversion of it into a cavity. Characteristic 

 changes are also observable just above the acetabulum. 



Three specimens of the humerus were collected in which the head 

 of the bone underwent similar transformation, i. e., pronounced flat- 

 tening, spreading and roughening. 



ARTHRITIS 

 Arthritis, Arthritis senilis, A. deformans (ordinary type), Spondy- 

 litis deformans 



Conditions not separable in the Peruvian skeleton, differing only 

 in grade and individually. 



Found thus far only in adults, and especially in the aging. 



Commenced in the Indian generally, first in some of the vertebrae 

 and at the same time, or soon after, on the lower articular surface of 

 one or both femora. 



In the vertebrae the process commenced generally in the lower 

 joints, very rarely in the upper. In the majority of instances it re- 

 mained restricted to the lowest joint. 



First signs : one or two " abrasion " spots on the posterior part 

 of the surface of one or the other condyle. There may also have 

 been early in the process slight concretory deposits on the surface 

 of the condyles. These conditions were soon followed by a slight, 

 uneven marginal redundancy (as if the end of the bone turned into 

 less solid consistency and articular surface was being forced out along 

 the margin) , which gradually extended and increased until it assumed 

 the character of a marginal, continuous, more or less irregular ex- 

 ostosis. As a rule it was the posterior part of one or the other 



