CARINATJE 



Gruiformes 



Brazilian Seriema. Cariarna cristata. Plate XIX. 



The dominant color of the fundus oculi is a dull-drab. Over the 

 lower quadrants of the eyeground run rather straight, dull-red, 

 choroidal capillaries that fade away as they reach the upper half 

 of the field. This region is also shot with a greenish-blue, muslin-like 

 film, which is probably a reflection by the retina of light rays from the 

 ophthalmoscopic mirror. Above the end of the disc is a small, 

 round depression, quite clear of any reflex. To the inner or beak 

 side of the eye is the circular macula, whose diameter is about three 

 times that of the cavity at the end of the disc. The centre of the 

 larger circle is quite clear, with the exception of a bright shimmer, 

 such as is sometimes seen about the human fovea. The circum- 

 ference of this circle is sharply defined, and has a bright ring around 

 it of glistening white. The optic disc appears as a long white oval, 

 with irregular margins. The black-brown corrugated pecten is 

 very large and long; it extends into the vitreous and almost touches 

 the lens with its club-shaped terminal. Very fine opaque nerve 

 fibres radiate at regular intervals from the whole papillary circum- 

 ference. 



Ardeiformes 

 European Night Heron. Nycticorax nycticorax. Plate XX. 



The eyeground is dull gray and covered with grayish-white dots. 

 The lower part of the fundus exhibits a number of dull-red choroidal 

 vessels, that run in a vertical direction. 



The optic disc is long and of medium width, with both extremities 

 rounded. Its centre is orange-red and covered with minute, brown 

 pigment dots. The pecten is deep brown and its outlines are well 

 defined the whole length of the papilla. Linear, grayish radiations 

 extend from the upper two-thirds of the optic entrance. 



The macula is situated quite close to and towards the upper- 

 nasal aspect of the disc. It is surrounded by an outer ring of whitish 

 lines, towards whose centre is a zone that closely resembles the sur- 

 rounding retina. In its exact centre, again, is a small fovea com- 

 posed of gray-white striae. 



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