PHYLOGENY OF THE PALZOGNATHA AND NEOGNATHA, 24 
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NERVOUS SYSTEM. 
THe BRAIN. 
Parker has shown that, compared with the brains of many Neognathw—Turkey, 
Emu, Goose, Pigeon,—the cerebral hemispheres in Apterya are proportionately of 
large size, and further peculiar is the way they overlap the cerebellum, in this respect 
bearing a very close resemblance to the Passeres. This overlapping conceals the 
grooves which mark the anterior region of the cerebellum, the hemispheres extending 
as far back as the flocculi. The posterior grooves are visible superficially, as in other 
brains. The pineal peduncle, in consequence of this overlapping, is inclined from 
the vertical position backwards. 
The position of the thalamencephalon is also peculiar, in that this region is tilted 
backwards, the lamina terminalis looking upwards, the foramen of Monro becoming 
postero- instead of antero-dorsal. 
THe Eye. 
The pecten is well developed in all the VPalwognathw, save Apterye. In 
Dromeus the number of its folds is reduced to four; in S¢truthio the lamelle are from 
14-20 in number. 
In Apterya the pecten is generally believed to be wanting in the adult, though 
present in the embryo. Dr. G. Lindsay Johnson, by a series of drawings recently 
exhibited at a soirée of the Royal Society, has shown that this is not really the case. 
‘The pecten is present in Apterya, though it assumes a peculiar form, being columnar, 
not fan-shaped, and plicated. In all other birds the pecten has two or more plications 
and is never conical—usually forming a vertical, plicated, densely pigmented septum 
dividing the disc into a right and left half, although its base expands over it so that 
very little of the disc is seen. The eye is small. Hence the apex of the pecten 
penetrates the vitreous to a distance nearly equal to that of the posterior surface of the 
lens from the retina. 
Dr. Johnson’s researches in this direction have related almost exclusively to the 
mammalian eye; and they have been most fruitful in results, enabling him to demon- 
strate a precisely similar “pecten” in the eyes of several Mammalia, that of the 
Golden Agouti—as he showed by means of drawings, exhibited at the above- 
mentioned soirée in June of this year—bearinug a most striking resemblance to that of 
Apteryx. 
JACOBSON’S CARTILAGES. 
These, according to Parker, are represented by a pair of vestigial rods of cartilage 
lying parallel to, and either immediately dorsad or slightly laterad of, the dorsal edge 
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