Figs. 310-315. — Skulls of fishes, to illustrate the mode of articulation of jaws and 
branchial arches, 310. Skull of Scy/lium. (After MARSHALL and sett gir. He 
tanchus (Notidanus). (After HUXLEY.) 312. Chimera. 2 313. Ceratodus. (Slightly m 
fied after HUXLEY.) 314. Polypterus. 315. Salmon. (After PARKER.) 
A. Articular. AG. Angular. BR. Branchiostegal rays. CHY., Ceratohyal. D. — 
Dentary. EAHY. Epihyal. LPH, LG. Epihyal ligament. PO, Epiotic. / Frontal. 
GHY, Glossohyal HHY. Hypohyal. AWM. Hyomandibular. /O. Interoperculum, 
F. Jugal. LC. Labial cartilages. MCK. Meckel’s cartilage. MP7. Metapterygoid, 
MSPT,. Mesopterygoid. MX. Maxillary. NM. Nasal. NC, Nasal capsule. O. 
lum. OC. Opercular cartilage. Of. Suborbital ring. /. Parietal. PAZ. e, 
PMX, Premaxillary. PO, Preoperculum. PTZ7O, Pterotic. P7Q. Palatoquadrate. 
PTY. Palatopterygoid. @Q. Quadrate. SQC. Supraoccipital. SZ. Supra-ethmoid. SA 
Symplectic. SO. Supraorbital. SP. Splenial UAC. Upper median (not 
frontal spine of male), 
Figs. 310, 314, 95 are regarded by HUXLEY as “hyostylic” (7.e. the hyoid element, 
HM, attached by ligaments to the jaw hinge, ens! an important part in su 
of the jaw; 311, a modified hyostylic condition; the hinder upper margin of Nad m- 
ing greatly enlarged, and attached by ligaments to the skull, is spoken of as “amphistylic"; 
312-313, were “autostylic,” ze. the upper jaw element fused with the skull. 
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