CARINATjE 



Passeriformes. A. Mesomyodi. Tyrannidoe. 



Derby Tyrant. Pitangus derbianus. Plate XLIX. 



The eyeground is blue-gray, everywhere sprinkled with minute, 

 gray dots. These dots are so closely packed on the upper half of the 

 fundus that they give it a distinct silvery appearance. Running 

 at right angles to either side of the optic papilla are numerous dull- 

 white opaque nerve fibres; they extend well across the eyeground. 

 At right angles to the optic disc towards the nasal side and a little 

 above its superior end is a dense, pale-blue, punctate mass that 

 appears to surround the fovea. A light blue reflex ring also 

 encircles this area. 



The optic nerve-entrance is long, narrow and white. Its centre 

 is stippled with a few brown pigment dots and it is bordered all 

 around with symmetrically placed black pigment granules. This 

 pigmented margin varies a little in individuals. The black-brown 

 pecten, long and narrow, extends well behind the edge of the pupil 

 so that a portion of it cannot be seen through the mirror. The upper 

 part is serrated but the lower half is more of the corkscrew type. 



Passeriformes. B. Acryomodi. UinuuUnidw. 

 European Chimney Swallow. Hirundo rustica. Plate L. 



The general color of the eyeground is warm gray, tinted slightly 

 with yellow or buff, and covered with minute, dull, yellowish dots. 

 Several pale orange (choroidal) vessels are seen near the upper ex- 

 tremity of the optic nerve-entrance. There are visible two macular 

 regions, one on each side of and above the upper end of the disc. 

 They show as small brown areas or dots in the eyeground. Sur- 

 rounding the temporal macula is a slight reflex, apparently com- 

 posed of minute, bright gray dots. The macula on the nasal side 

 is quite devoid of this reflex-ring. 



The optic papilla, long and narrow, tapers at its upper end. On 

 either side of the disc, and at right angles to it are a few, fine, dull- 

 gray opaque nerve-fibres. 



The chocolate-brown, convoluted pecten is quite narrow at its 

 junction with the optic nerve, but it gradually becomes wider and 

 more massive as it approaches the lens. 



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