CARINATjE 



Passeriformes. B. Corvidae. 



Common British Blackbird. Turdus merula. Plate LVII. 



The general tint of the eyeground is a slaty-gray with a uniform 

 sprinkling of tiny, white dots. There is no visible macular region, 

 hut the whole fundus is covered and its coloring greatly modified by 

 numerous linear opaque fibres that arise from the disc margins 

 throughout and run across the entire fundus to the extreme periphery. 

 A few, faint, yellow-red choroidal vessels are seen on either side of 

 and parallel to the moderately long and narrow papilla. The upper 

 two-thirds of the disc is about half covered by the club-shaped 

 pecten, which is composed of very few folds. The massive, chocolate- 

 colored, posterior end of the pecten entirely obscures the lower third 

 of the disc, while the upper half of the former has a light brown mar- 

 gin on its nasal aspect, and seems to be only in part attached to the 

 nerve-head beneath it. 



Raven. Corvus corax. Plate LVIII. 



The eyeground is a light fawn sprinkled with dots about three 

 shades darker than the ground color. Mixed with the dark dots are 

 a number of white ones, seen especially when a strong light is thrown 

 upon the fundus. About three disc-breadths from the upper end 

 of the disc on the inner side is a well marked, bright reflex of a green- 

 ish-blue tinge. It is irregularly oval in shape and seems to be com- 

 posed of a number of very fine fibres. In the centre of the reflex is 

 the macula, a small, dark, crater-like depression, brown in color. 

 The disc is chalky white, and gives one the impression that it is 

 composed of many opaque nerve fibres packed closely together. 

 From the disc margins there radiate a number of fine optic nerve 

 fibres that extend across the eyeground. In the lower part of the 

 fundus, associated with a number of orange-red dots, are a few orange- 

 red choroidal blood-vessels, several of the latter being distributed 

 along either side of the disc. The pecten is very thin and narrow 

 at the disc but assumes a club-shape as it approaches the lens, where 

 it is darker in color. It comes well forward and appears at times 

 to press against the posterior capsule of the lens. 



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