tail fin

Tail-fin thrice depth of tail-musculature, which extends beyond posterior end of tail-fin giving sword-tail appearance (Fig. 2).

His dorsal stood up straight and stiff, and the big sickle-shaped tail-fin wove to and fro behind.

The tail-fin, which is deepest at mid-length, extends to the back of the head and is flecked with brown.

These specimens are olive-brown above with cream-colored spots on the flanks; the dorsal tail-fin does not extend onto the body.

The dorsal and ventral fins are often divided into two or more parts, and the tail fin is commonly distinctly forked.