19 
bird and the blanched specimen that may easily escape recognition 
aftei death. To Mr. Head and Hr. Lindsay Johnson are due the 
discovery—as yet unheeded by text-books—that every bird, the Kiwi 
included, has a well-developed pecten. 
THE CARINATJE. 
The ocular funclus of the common Blackbird—Merula vulgaris. 
Everyone is acquainted with this member of the large order of 
Passeres—his yellow bill, his yellow-edged eyelids, and his jet-black 
body. I have chosen him as a fair example of a quick-sighted, in¬ 
sectivorous bird, with monocular vision and daylight habits. These 
are all reflected in his beautiful uniform, bluish-gray fundus, his 
canoe-shaped, whitish optic nerve entrance, and his black-brown, 
club-shaped pecten. A lateral view of his pectinate body shows that 
Fig. 7.—Macroscopical, postmortem diagram of the left eye and orbit of the 
tern (Sterna hirundo). N, optic nerve entrance; P, pecten; Ft, At, fovea and 
area temporalis; Fn, An, fovea and area nasalis ; Ah, band-like area. (Slonaker.) 
it arises by a rather slender pedicle that covers less than one-half the 
optic papilla. The body then spreads out and, projecting toward 
and almost reaching the posterior surface of the. crystalline lens, 
gradually enlarges until it presents to the ophthalmoscope a dumb¬ 
bell or “nine-pin” appearance. One will also observe the regularly 
placed opaque nerve fibers covering the whole fundus, as well as the 
streaks of reddish chorioidal vessels showing through the gray-white 
background. There is no macular region differentiated from the 
general fundus coloration, although, in common with other birds. 
Merula vulgaris has a microscopically deep and well-defined fovea. 
The ocular fundus of the Tawny Owl. Syrnium aluco. The eye¬ 
sight of the whole owl family should be of consuming interest to the 
ophthalmologist because of the almost human arrangement of his 
