THE SERPENT HEADS 2779 



THE SKRPENT HEADS Family OPHIOCEPHALID^ 



Mainly characteristic of the Oriental region, although also represented in Africa, 

 the fresh-water fishes known as serpent heads are interesting not only on account 

 of their structure, but likewise from their peculiar habits. They form a single 

 family, constituting a sectional group by itself, and represented by two genera, in 

 one of which {Ophiocephalus) pelvic fins are present, while in the second (Oianna) 

 they are wanting. As a family, the serpent heads are characterized as follows: 

 The body is elongate and covered with medium-sized scales; all the fins are devoid 

 of spines, the anal and single dorsal being long and low; and there is an additional 

 cavity above the proper gill chamber, although this is not furnished with supple- 

 mental gills. The depressed head is covered with somewhat plate-like scales, and 



STRIATED SERPENT HEAD. 

 (One-ninth natural size.) 



has the eyes lateral and the gill openings wide; each gill chamber containing four 

 gills, while teeth are present on the jaws, palatines, and vomer. If present, the 

 pelvic fins are thoracic in position, and composed of six rays. The lateral line is 

 sharply curved or almost interrupted, and an air bladder is present. Of the typical 

 genus there are some thirty existing species, having a distribution coextensive with 

 that of the family, and in Asia ranging over Baluchistan, Afghanistan, India, 

 Ceylon, Burma, China, Siam, and the Malay Archipelago; the figured species (O. 

 striatus] being common to such distant localities as India and the Philippines, and 

 at times reaching as much as a yard in length. The second genus, Channa, is 

 represented only by a single species from Ceylon and China. In a fossil state these 

 fishes have been identified from the Pliocene rocks of the Siwalik hills in North- 

 eastern India. 



In India the serpent heads are found in rivers, ponds, tanks, and swamps, 

 many of them seeming to prefer stagnant to running waters. Day writes that 



