THE CRANIUM, 19 
bones, forming the roof and sides of 
the anterior portion of the cranium, 
mecting both dorsally and ventrally. 
They unite suturally; posteriorly with 
the parietals by the transverse coronal 
suture, ventrally with the orbito-sphe- 
noids and pre-sphenoids, and anteri- 
orly with the jugals, lachrymals, max- 
illz2, and nasals. The most .anterior 
portion is produced, and passes _ be- 
tween the nasals and maxille. Lat- 
erally each is slightly produced down- 
wards and outwards into a process 
above the orbit, the supra-orbital 
process. 
iv. The /achrymals are two small bones 
forming part of the anterior walls of 
the orbit. They lie between the fron- 
tals, maxille and jugals. Each is 
perforated by a small aperture for the 
passage of the lachrymal duct. The 
lachrymal is probably homologous 
with the antorbital bone of fishes, 
which is the most anterior of a series 
of sensory canal bones bordering the 
orbits. 
d. The ethmoidal region is situated anterior to 
the cranium, and forms the dorsal and poste- 
rior division of the facial portion of the skull. 
i, The mes-ethmoid consists of two parts, 
