EXPLANATION OF PLATES. 

 Index Letters. 



A. Superficial portion of adductor mandibulae. 



A^. Mandibular portion of adductor mandibulae. 



A^Ay Deeper portion of adductor mandibulae. 



Aap. Adductor arcus palatinus. 



al>. Nervus abducens. 



Abds. Abductor superficialis muscle of the pectoral fin. 



Abdp. Abductor profundus muscle of the pectoral fin. 



acvfi: Foramen for anterior cerebral vein. 



Add-ff. Adductor profundus. 



Adds. Adductor superficialis. 



agl. Ramus anterior glossopharyngei. 



Ah. Adductor hyomandibularis. 



aJifr. Foramen for the arteria hyoidea. 



ANT. Antorbital (Sag.), preorbital (Bridge). 



Ao. Adductor operculi. 



ART. Articular. 



AS. Alisphenoid. 



BBi--'> . First to fourth basibranchials. 



bf. Ramus buccalis facialis. 



bf. io^-9 . Branches of buccalis facialis to sense organs of infraorbital 



canal. 



bf. so. Branch of buccalis facialis to first sense organ of supraorbital 



canal. 



BJI. Basihyal. 



BRG. Branchiostegal rays. 



BS. Basisphenoid. 



cb. Ciliaris brevis. 



CB I- V. First to fiftii ceratobranchials. 



cc. Common carotid artery. 



CH<i-,CHp. Distal and proximal ossifications of the ceratohyal. 



cl. Ciliaris longus. 



csa. Anterior semicircular canal. 



cse. External semicircular canal. 



csp. Posterior semicircular canal. 



D- Dentary. 



dgr. Dilator groove. 



dmp. Dorso-median pocket of intermuscular septum. 



Do. Dilator operculi. 



dpp. Dorso-posterior pocket of intermuscular septum. 



ea I-IV. Efferent arteries of first to fourth branchial arches. 



ECP. Ectopterygoid. 



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