SKELETON. 661: 
maxilla, jugal, and quadrato-jugal, the last abutting on the 
movable quadrate. 
Of the membrane 
bones on the side of the 
skull, the lachrymal in 
front of the orbit, and 
the squamosal between 
the quadrate and the 
parietal, are the most 
important. 
On the roof of the 
mouth, the basisphenoid, 
which lies just in front 
of the basioccipital, is 
covered over by a mem- 
brane bone—the basi- 
temporal. In front of 
this is a sharp “basi- 
sphenoid rostrum” or 
parasphenoid, also a 
membrane bone. Artic- 
ulating with the quadrate 
and with the rostrum 
are the pterygoids; in 
front of these lie the 
palatines. The vomer 
is vestigial. The bony 
front of the palate is 
formed from inward ex- 
tensions of the  pre- 
maxille and maxilla. 
The interorbital septum 
is formed chiefly from Fic. 364.—Under surface of gull’s 
the mesethmoid, but also skull. —From Royal Scottish Museum, 
from the presphenoid. Edinburgh. 
From the tympanum to «., cae 4.¢., basitemporal; 4.s., basi- 
: sphenoidal rostrum; 4f., pterygoid; pa. 
the inner ear extends the palatine; z., vomer 3 bmx, premaxilla; aise, 
rod-like columella. The mala | fs iagel getty uatmaeriaial yey 
lower jaw originally con- 9% 
sists of four membrane bones—dentary, splenial, angular, and 
surangular ; and one cartilage bone—the articular... The 
