SKELETON 



243 



is reduced; the post-temporal is vestigial, and suspended in a 

 ligament ; a very small cleithrum surmounts the clavicle, and the 



FIG. 212. 



Pectoral girdle of A, Ceratodtis ; B, Polypterus. Ventral view. (From Gegenbaur, Vergl. 

 Aiiat.) Cl, clavicle ; Cl', cleithrum ; g, articular facet for fin-skeleton. 



cartilage is subdivided into a ventral median piece, and two more 

 .dorsal pieces supporting the fins. 



