CARINATjE 



Ardeiformes 



European Bittern. Botaurus stellaris. Plate XXI. 



The eyeground, mostly mouse-colored shading to yellow, is 

 sprinkled with small, dull-white dots. Almost immediately above 

 the upper end of the optic nerve entrance and towards the nasal 

 side of the disc is the macular area. The fundal dots at this point 

 are much duller in tone and incline towards a dull buff color. The 

 region of the macula, enclosed by two circles, one within the other, 

 is also characterized by the presence of very short, bright, bluish- 

 green lines radiating from the centre of the fovea. 



The optic disc is ovoid, blunt at its upper extremity, and appears 

 as if its longer margins describe a series of small curves correspond- 

 ing to the folds of the pecten. The disc on either side of the root of 

 the pecten is dull-brown; near by are small, orange-red choroidal 

 capillaries. The papillary margins are quite white and, in contrast 

 with the shadow cast upon the neighboring field by the dark pecten, 

 the disc stands out in sharp contour. Extending a short distance 

 over the fundi and about the optic disc are a few opaque nerve fibres. 

 The pecten, convoluted, with serrated margins, and of the usual 

 chocolate-brown color, extends below the lower end of the optic disc. 



Boat-billed Night Heron. Cancroma cochlearia. Plate XXII. 



The eyeground is dull-red and covered with orange-red dots. 

 These punctate deposits are intermixed on the upper half of the 

 fundus with smaller and brighter dots of a grayer tone. On the 

 lower half and on each side of the optic nerve are a few orange-red 

 choroidal vessels, that run in a vertical direction, parallel to the 

 long axis of the disc. The macula is situated towards the nasal side 

 of the nerve head. This sensitive area is rather brighter in color 

 than the surrounding field, and several white dots are included in it. 

 These small dots, however, are noticeable only when the light of the 

 mirror is reflected on the region in certain directions. Rather a 

 bright, irregular and linear reflex surrounds the macular region, 

 which is very sensitive to light. There is a long, narrow papilla with 

 rounded extremities. It appears as if it were composed of short, 

 white fibres, surrounding an orange-red centre covered with minute, 

 dark-brown pigment grains that form a network over the whole red 

 area. Extending from each side of the disc across the retina are a 

 few dull-gray, opaque nerve fibres. 



The pecten can be traced the whole length of the disc; it is dark 

 brown in color and grooved spirally like a corkscrew. It does not 

 appear to come far forward towards the lens, and its union with the 

 nerve head can readily be traced. 



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