Q. J. G. S. vol. xlviii.] 



iTo face^. 148, 



POLACANTHUS, sp. 



Fig. 1. 



TioL, 2. 



Explanation of Figures. 



Outer (fig. 1) and inner (fig. 2) views of the imperfect right ilium and sacral 

 ribs, with part of the dermal armour. \ natural size, a = dermal shield ; 

 b = tuberosity for ischium. 



