H8 



5 = |201j and / = j012j, well developed; there are commonly only 

 two faces of the form t present. 



Further: o = |121i, siiowing among all pyramids present (he lar- 

 gest faces; w = jlll|, somewhat smaller than o; // = {122!, very 

 small, bnt giving distinct images; w = \\\()\ and /> = |12()i, very 

 small and suitsidiary, bnt measurable. 



