FIGURE 4. 4.1 Bivariate analysis involving degree of involution (U/D) vs. shell diameter of Umiaites (solid square) and Proniceras (solid diamond) of the world. Note similar degree of involution. 4.2. Bivariate analysis involving degree of inflation (W/H) vs. shell diameter of Umiaites rajnathi and different species of Proniceras. Note scatter of points of early whorls of U. rajnathi correspond with those of Pronicers spp. Sources other than present study materials are Krishna et al. (1994), Imlay (1939), Collignon (1960) and Wright et al. (1996).