As mentioned before, the cephalic (head) shield is subdiveded into several
regions.
Cephalon dorsal
(Zlichovaspis sp.)
The glabella is the significant elevation in the middle of
central cephalic shield, occipital bounded by the occipital furrow. Furrows
(lateral furrows) are perceptibal on the Glabella, seems this furrows are
medial incisting into the glabella extending greater or lesser, thus
partitioning lateral lobi. The posterior occipital lobe, adjacent the anterior
axis, is called preoccipital lateral lobe.
The cranidium (Gr.- Skull) is formed by Glabella and solid
cheeks (Fixigenae). The Cranidium as central part of cephalic shield is
restricted from cephalons rest by sutures. The sutures are dividing the
glabellas lateral part to the solid cheeks (Fixigenae) already mentioned and
free cheeks (Librigenae). The compound eyes (provided as species-specific
present) are placed at lateral cheeks area. These eyes are permanently connected
with the free cheeks at many of these species.
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