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Proceedings of the Pioyal Society 
passed almost transversely inwards, and joined the supero-internal 
angle of the occipital lobe close to the longitudinal fissure. It was 
superficial in its entire extent, and consequently bridged across 
the external perpendicular fissure. From its position and connec- 
tions it must he regarded as the homologue of the superior con- 
necting convolution of G-ratiolet. This brain, therefore, furnishes 
another example to those already recorded by Professors Kolleston 
and Marshall of the occurrence of this convolution on one side of 
the brain of the Chimpanzee, though in the opposite hemisphere 
to that found in their specimens. 
fissure. 
In the brain (^) the amount of variation was still more strongly 
marked. On the right side the postero-parietal lobule gave off from 
its outer and posterior part a superficial convolution (a, fig. 1) -j^oths 
of an inch broad, which was almost immediately joined on its deep 
surface by a slender process from the superior angle of the bent 
convolution, the place of junction being concealed by the imper- 
fectly defined occipital operculum. This convolution, then, passed 
across the external perpendicular fissure, inclined inwards, till it 
