Pi /Al FISHES CHAP. 
ossified to form the articular, which has a deeply concave surface 
mks ar 
Fic. 123.—A, view of the left side of the skull of a Salmon ; B, the left half of the primary 
upper and lower jaws, and the hyoid arch. The cartilage is dotted. an, Angular ; 
ar, articular ; b.hy, basi-hyal ; 67.7, branchiostegal rays ; ¢, cranium ; c.h, cerato- 
hyal ; ¢.or, cireum-orbital bones ; d, dentary ; d.eth, dermal mesethmoid ; ep.h, epi- 
hyal ; ep.o, epiotic ; eth.p, ethmo-palatine process ; /, frontal ; h.hy, hypo-hyal ; 
hym, hyomandibular ; 7t.vp, inter-operculum ; 7, jugal; mks, Meckel’s cartilage ; 
mpg, mesopterygoid ; mt.pg, metapterygoid ; ma, maxilla; n, nasal; op, operculum ; 
op’, condyle on the hyomandibular for the operculum ; ord, orbit ; p, parietal ; pa, 
palatine ; p.mx, premaxilla; p.op, pre-operculum ; pt, pterygoid ; pt.o, pterotic ; 
q quadrate ; so, supra-occipital ; s.op, suboperculum ; sp.o, sphenotic ; s.¢, supra- 
temporal (or squamosal) ; st.hy, stylo-hyal; sy, symplectic ; w./.c, u.lc’, upper 
labial cartilages ; w./.c?, second upper labial. (From W. K. Parker.) 
for articulation with the quadrate; and below this there is a small 
membrane bone, the angular. The rest of the cartilage is partially 
