344 Proceedings of the Boyal Society 
very distinct. The ali-sphenoid was pointed superiorly, and sepa- 
rated from the parietal by the articulation of the squamous part of 
the temporal with the frontal. This arrangement was also traced 
in the chimpanzee, and seems to be the rule in the crania of these 
anthropoid apes. In the orang, on the other hand, the articulation 
of the ali-sphenoid superiorly varied in different specimens. Of four 
crania examined, — in one the ali-sphenoid on each side articulated 
with the corresponding parietal ; in one a tongue-shaped process 
of the squamous part of the temporal articulated with the frontal, 
and cut off the ali-sphenoid from the parietal ; whilst in the other 
two crania, the ali-sphenoid articulated with the parietal on one 
side of the skull only, for on the other side a tongue-shaped process 
of the temporal was intercalated between them. In two crania of 
the gibbon, again, a well-marked articulation existed between the 
ali-sphenoid and the parietal on both sides of each skull ; whilst in 
a third, on the left side, a narrow tongue of the temporal, reach- 
ing the frontal, was intercalated between the ali-sphenoid and the 
parietal, and on the right side the tongue of the temporal projected 
into, but not quite across, the ali-sphenoid, so that the latter was 
still, though slightly, in communication with the parietal. If the 
tongue of the temporal had passed quite across the ali-sphenoid, 
then the upper end of this bone would have been cut off, and would 
have formed a triquetral bone in the temporo-parietal suture. In 
man, the rule is for the ali-sphenoid to articulate with the anterior 
inferior angle of the parietal, and thus to cut off the frontal from 
the squamosal ; but exceptions not unfrequently occur, and crania 
seen by the author were referred to, not only in the Negro, Hot- 
tentot, Caffre, Bushman, Sandwich Islander, and Australian races, 
but also in Hindoos, Ceylonese, and Europeans (French, Scotch), 
in which a tongue-like process of the squamosal passed between 
the ali-sphenoid and parietal to articulate with the frontal.* 
^ Although it would appear from an examination of a considerable number 
of crania of old-world monkeys that the rule is in them for a tongue-shaped 
process of the temporal to articulate with the frontal, and consequently to cut 
off the ali-sphenoid from the parietal, yet several crania have been noted in 
which the ali-sphenoid and parietal had a well-marked articulation with each 
other. Some of these skulls had unfortunately not been named, and it was 
difficult exactly to identify them ; but in a skull of Semnopithecus entellus, and 
in one of Macams ciynomolgus, the ali-sphenoid articulated on both sides with 
