THE FISHES OF MALABAE. 
229 
margin concave. Wlien the moutli is closed the mandible is laterally concealed by the upper jaw. 
Preorbital narrow. Preopercle rather wide, lower limb almost horizontal. Opercle nearly semi¬ 
circular posteriorly. Sub- and interopercles small. Upper surface of head nearly flat, with a 
central rather wide but very shallow depression, extending from opposite the preopercle to opposite 
the anterior margin of the orbit: for its anterior third it has a central longitudinal elevation. 
Nostrils, the anterior round, the posterior oval, situated midway between the eye and snout. The 
left branchiostegous membrane partially overlaps the right. 
Teeth—Yilliform in both jaws, in several wide bands in the mandibles : on the vomer there 
is a heart-shaped spot: also villiform ones on the palate, pterygoids, and sphenoids. 
Fins—Pectorals in the lower fourth of the body, under the posterior border of the subopercle : 
dorsal midway between the snout and base of caudal: ventral under the origin of the dorsal, and 
the anal a short distance behind the posterior margin of the dorsal. Dorsal high in front, upper 
margin rather concave, last half of the posterior ray long, and reaching to opposite the end of 
the anal; the third ray the longest in front, the last ray but one equal to a little more than a 
third of its height. Pectoral pointed. Ventral with an elongated scale at its base. Anal with 
the fourth and fifth rays the longest; the fin is highest in front, and concave along the first part 
of its lower margin, then parallel with the abdomen, its last ray a little prolonged. Caudal deeply 
lobed, the lobes rather more expanded in the immature than in the adult fish. 
Scales—Cycloid, longest diameter from above downwards, posterior fourth of exposed por¬ 
tions smooth, shining, and covered by membrane. No scales on the head. A few small ones over 
the base of the anal fin. v 
Lateral line—Is formed of a single tube in each scale, which branches off into six or eight 
smaller ones, and in the last half of the scale into from eight to twelve narrow channels, which 
proceed to its posterior margin. It first curves a little downwards; opposite the commence¬ 
ment of the dorsal it proceeds direct in the adult, but in the immature is slightly convex opposite 
the dorsal, from whence it proceeds straight to the caudal. Centre of the scales raised in the 
adult. 
Colours—Summit of head dark olive, back bluish-green in the adult, lighter in the immature. 
Abdomen silvery, with bluish reflections. The margins of the scales of a brilliant silver, as is also 
the lateral fine and the sides of the head. The centre of the jaws black. Dorsal and caudal 
greyish, minutely dotted with black, and the margins blackish, as is also the last elongated dorsal 
ray. Pectoral, ventral, and anal diaphanous, with some fine black dots, the last anal ray darkish. 
Eyes silvery, with the orbital margin of a darkish tint. The pupils oval, pointing downwards. 
It is occasionally captured in the mouth of the river at Cochin, but much more commonly 
found in the tanks, and especially in the fort ditch. Amongst many specimens examined at 
Cochin, no difference existed in the number of scales in the adult and young fish, as noted by 
Cantor in the Straits, and the filamentous portion of the last dorsal was as long in the adult as in 
the young specimens, but the comparative size of the eye larger in the former than in the latter. 
Is considered good eating, but is bony. It makes tremendous springs out of the water. It is not 
river fish, but during the monsoon it is caught both there and in the sea. 
Habitat—Fresh waters and estuaries of India, Ceylon, Malaysia, China, and Polynesia. 
