Pomona College, Claremont, California OY 
The parietals (6) lie in contact with one another for their 
entire length. They are smaller than the frontals, however, they 
form less of the dorsal surface of the skull than their real size 
would warrant, since at their articulations with the frontals these 
bones extend down over them. Posteriorally each parietal articu- 
lates with the occipital, and posterio-laterally with the occipital and 
the sphenethnoid. 
The occipitals (10) are the most posteriorally placed bones in 
the skull. The dorsal surface of each is more or less regular, di- 
verging toward the median line to form a short rather slender 
process which articulates with the other occipital. Anteriorally 
the occipital connects with the parietal while posteriorally on the ex- 
ternal side, it articulates with the squamosal. The ventral surface 
of the occipital is very irregular and the articulations with other 
bones are not continuous. Posteriorally on the external side it 
diverges to form a short process, which unites with the squamosal 
and forms the posterior corner of the skull. On the inner aspect 
of the ventral surface, adjacent to the squamosal articulation, is a 
projecting knob-like process with which the ptergoid articulates. 
Bs eo 
ry . \ } e td ie << — ) 
\ 5 he) 
\ 
/ 
7 J 
[i 9 
The most posterior portion of the occipital toward the median line, 
diverges to form a knob-like condyle which articulates with the 
first vertebra. Anteriorally the occipital articulates with the par- 
asphenoid and anterio-laterally diverges to form a projection which 
articulates with the sphenethnoid. 
The squamosal (9) is a peculiar T-shaped bone, standing in an 
almost vertical position in the skull. The bar of the T, forms a 
part of the dorsal surface of the skull and articulates at the anterior 
end with the frontal bone; at the posterior end with and up past the 
point where the stem of the T diverges, it articulates with the occip- 
ital bone. The stem of the T projects ventrally almost at a right 
angle, and articulates with the ptergoid and the quadrate. 
