Chapter XIII 



COLORED DRAWINGS OF THE FUNDUS 

 OCULI OF BIRDS 



Efforts to duplicate exactly the paintings made by 

 Mr. A. W. Head for this Atlas have been attended 

 by difficulties that have arisen chiefly from the fact 

 that precise duplication of minute details and shades 

 of color (of minor importance in the usual forms of 

 color reproduction) were regarded as essential in this 

 investigation. However, these impediments were, 

 after many trials and the exercise of much patience on 

 the part of the publisher's officials, finally removed and 

 the writer now believes that the following plates faith- 

 fully represent not only the varied and beautiful 

 coloration but the complex tissue formations revealed 

 by the ophthalmoscope in the ocular background of the 

 avian and reptilian species herein depicted. 



For the convenience of the reader a brief description 

 of each fundus drawing has been placed on the page 

 opposite each plate, a more complete description of 

 the ophthalmoscopic appearances, as well as their 

 relations to other fundus views, being given in Chapters 

 IX and XII. 



11!) 



