DISEASES OF THE IRIS AND CILIARY BODY I2i 



''Animals in which the eyes have been experimented on 

 by inoculation die of general tuberculosis due to infec- 

 tion starting from the eye" (Duane). 



Tumors of the iris and ciliary body are benign and 

 malignant. The corpora nigra, which is normal, of 

 course, is an example of the so-called melanomata which 



Fig. 27.-Sarcoma of the left orbit. (Dr. Geo. H. Robberts' case.) 



occur in the iris. It springs from the pigment layer at 

 the margin of the pupil. Another form is an excess of 

 pigment springing from the iris stroma and projecting 

 into the anterior chamber. They develop to a certain 

 size and may remain stationary. Portions of the pig- 

 ment mass may become loose from the main body and 

 fall into the anterior chamber. They are benign in 



