SKELETON. 553 
{c) Along the floor: basi-occipital, Jarasphenotd, vomers. 
(@) Around the ear on each side: sphenotic, pterotic, and épiotic 
(above), prootic and opisthotic (beneath). 
4e) In front of and around the orbit: parethmoid, Jachrymal, 
orbitgls. 
Thus the haddock’s skull shows in two respects an ad- 
Fic. 295.—Disarticulated skull of cod. 
S.O., Supra-occipital ; Pa., parietal; 77, frontal; 47.Z., meseth- 
moid; WV., nasal; P.#., parethmoid; Oz, otics; #.O., ex-occi- 
pital; B.O., basi-occipital; Pa.S., parasphenoid; V., vomer; 
L., lachrymal; ord., orbitals; A.4Z., hyomandibular; S., 
symplectic; Q., quadrate; Pz., pterygoid ; w.pz., metaptery- 
goid; ms.f¢., mesopterygoid; PZ, palatine; AZx., maxilla; 
Pmy., premaxilla; Av., articular; Am., angular; D., dentary; 
u.h., urohyal ; 2.4., hypohyal; ¢.4., ceratohyal ; ¢f.4., epihyal ; 
i.h., interhyal; Of., opercular; S.of., sub-opercular; z.op., 
inter-opercular ; 2.0%., pree-opercular. 
vance upon that of the skate: first, in the ossification of the 
primitive cartilage ; and second, in the addition of membrane 
bones. Of the latter, the parietals and frontals cover over 
the spaces which in the skate form the fontanelles. 
