The spinous armature of the opercle and the two spines of the first dorsal fin constitute the weapons.
The soft rays of the dorsal fin are blue, with orange between.
He was twenty-five feet in length, and had a dorsal fin that stood up like the sail of a small boat.
His first dorsal fin is large and drawn out into a long filament.
The dorsal fin is very small, falcate, and located in the latter half of the back.
A dorsal fin is present in the rorquals but absent in right whales.
From time to time a portion of the back and dorsal fin appeared at some distance from the head.
In one large group known collectively as the "anglers" the first spine of the dorsal fin hangs over the mouth.
Her dorsal fin opens out and is cautiously raised, while her eyes greedily watch the movements of the nimble little fish.
In the genus Pontoporia the dorsal fin is well developed and falcate.