134 
THE FISHES OF MALABAR. 
Genus POLYACANTHUS, Cuv. and Val. 
Branchiostegals, six: pseudobranchiae none. Body oblong, compressed: opercles without spines: 
sub- and interopercles and preorbital serrated. A superbranchial organ as in the Genus Anabas. Eyes 
lateral. Moutb small, oblique, little protractile. Branchial arcbes with toothed tubercles. One dorsal 
fin, tbe spinous portion much more developed tban the soft. Anal spines numerous, and more developed 
than its soft portion. Yentrals of one spine and five well developed rays, some of which are usually 
elongated. Teeth villiform in both jaws. Scales ctenoid. Lateral line interrupted, partially or entirely 
absent. Air bladder simple. Pyloric appendages few. 
Polyacanthus cupanus. 
Polyacanthus cupanus, Cuv. & Val. vii. p. 357 ; Gunther , Catal. iii. p. 381. 
Caringanah, and Wunnuttee, Mai. 
B. vi. D. 1 % 15 . P. 10. Y. i A. 1 jy 8 . C. 13. L. 1.30-32. L. tr. f. 
Length of head 1, of pectoral jh, of caudal nearly U of base of dorsal spines nearly of 
base of soft dorsal A> of base of anal spines above of base of soft anal of the total length. 
Height of head of body of hard dorsal A °f soft dorsal 1, of ventral 1, of anal spines A °f 
anal rays A °f the total length. 
Eyes—Diameter 1 of length of head, 1 diameter from end of snout, 2 diameters apart. 
Body rather oblong*, and compressed. 
Mouth transverse ; lower jaw rather the longest: intermaxillaries slightly protrusible. Angle 
and posterior half of the horizontal margin of the preopercle finely serrated. The opercle ending 
in a fleshy point. Subopercle very finely serrated, also the posterior half of the interopercle. Pre- 
orbital serrated in its external extremity. Openings of the nostrils wide, approximating, the 
posterior being close to the anterior superior margin of the orbit, and the anterior close to the 
edge of the snout. 
Teeth—In two or three rows of villiform ones in the upper jaw: in several opposite the 
symphysis of the lower, and in two rows along either side. 
Pins—The dorsal commences above the posterior third of the pectoral, and terminates 
opposite the last spine of the anal, where the rays are elongated and the fin becomes pointed: the 
ventral arises under the pectoral, its first ray is elongated into two filaments which reach to opposite 
the eighth anal spine : the anal begins opposite the anterior third of the pectoral. The dorsal 
spines increase in length to the last, and there exists a groove along the back for their reception 
into which they can be laid flat: the last spine equals the distance between the posterior extremity 
of the orbit and the posterior extremity of the opercle : the last rays are likewise longer than the 
first, and extend to opposite the anterior third of the caudal fin. The anal is similar to the dorsal, 
but continued further posteriorly, its rays are longer than its spines. The central caudal rays are 
elongated. 
Scales—Ctenoid, covering the body, head, and jaws, whilst some fine ones are also present 
along the base of the dorsal and anal rays. 
Numerous glandular openings exist on the head, one is present at the angle near the centre 
of the lower margin of the preopercle, another about the centre of its vertical limb. 
Lateral fine—At first on the fifth row, then on the fourth to the fourteenth scale where it ceases. 
Colours.—Deep rifle green with the prolonged ray of the ventral of a bright scarlet. Caudal 
barred in fines of spots, as is also the dorsal especially in its soft portion. A round black spot 
exists at the base of the caudal. Eyes hazel. 
