ClipArt ETC
"Lateral view of dogfish (Scyllium catulus). Note ventral mouth with naso-buccal groove, heterocercal tail, and unpaired fins. gs., Gill-slits; pc., pectoral fins; pv., pelvic fins." -Thomson, 1916

Dogfish

"Lateral view of dogfish (Scyllium catulus). Note ventral mouth with naso-buccal groove, heterocercal…

"Larva of Polypterus. e.g., Large external gill of the hyoid arch; Pc., pectoral fins; Pv., pelvic fins. The larva is drawn in a very characteristic attitude." -Thomson, 1916

Polypterus

"Larva of Polypterus. e.g., Large external gill of the hyoid arch; Pc., pectoral fins; Pv., pelvic fins.…