208 



P TER1CHTH YOMORPHI 



in the Coccosteomorphi, are evidence of wide divergence. On the 

 other hand, the Pterichthyomorphi have much in common with the 



( occ 



Fio. 181. 



Pteriehthys Milleri, Ag. Dorsal (A), ventral (B), and left lateral aspects (C); restored. 

 (After Traquair, from A. S. Woodward, Proc. Geol. Assoc.) a.d.l, anterior dorso-lateral,; ag, 

 angular ; a.m.d, anterior median dorsal ; a.v.l, anterior ventro-lateral ; c, central ; d.a, dorsal 

 anconeal ; d.ar, dorsal articular ; e.l, extra-lateral ; e.m, external marginal ; i.m, internal 

 marginal ; I, lateral ; l.oce, lateral occipital ; m, median ; m, in, in, in, marginals ; m.occ, median 

 occipital ; m.v, median ventral ; inx, maxilla ; o, ocular ; p.d.l, posterior dprso-lateral ; pm, pre- 

 median ; p.m.d, posterior median dorsal ; ptm, posthiedian ; p.i'.l, posterior ventro-lateral ; si, 

 semilunar ; t, terminal; v.a, ventral anconeal ; v.ar, ventral articular. Dotted lines indicate 

 the course of lateral-line canals. 



