AdPEKSER GLABER. 



385 



together (Fig. 175). At the back of the head, towards the median line, are two 

 small unequal spike-shaped epiotic shields, which have their broad bases joined 

 to the first dorsal shield. A median supra-occipital shield, somewhat Y-shaped, 



Fig. 174. ACIFENSER GLABER (MARSILIUS). f 



extends forward from the epiotic shields like an inter-parietal element, and 

 divides the two largest scutes of the head from each other at their posterior end. 

 These large plates are the parietal scutes. They exceed half the length of the 



Fig. 175. UPPER SURFACE OF HEAD OF 



ACIPENSER GLABER, SHOWING DERMAL 

 SCUTES. 



Fig. 176. UNDER SIDE OF HEAD OF ACI- 

 PENSER GLAIiER, SHOWING MOUTH AND 

 BARBELS, AND PORES ON THE UNDER 

 SIDE OF THE ROSTRUM. 



head, and are longer than in any other species. Flanking them laterally, are 

 the similarly long squamosal shields, which are widest in front. Another 

 pair of shields stretches forward from the angle between the parietal and 



