MALACOPTERYGII 555 



and the anal is much elongate and confluent with the caudal, 

 which may be regarded as aborted. The scapular foramen 

 is entirely in the scapula. The air-bladder is very large, with 

 several divisions, forked in front and behind, and prolonged 

 along each side of the caudal region ; its extraordinary condi- 

 tion has been described by Bridge. 1 



These Fishes live in marshes and lakes, fresh-water or brackish, 

 and feed on worms and insects. Nothing is known of their 

 breeding habits and development. 



Two genera : Notopterus, with a dorsal fin and 6 to 9 branch i- 

 ostegal rays three species from India, Burma, and the Malay 

 region, and one from West Africa ; Xenomystus, without dorsal 

 fin and with only 3 branchiostegal rays, the unique species in- 

 habiting the White Nile and West Africa. Eeniains of Noto- 

 pterus have been found in the marl slates (Tertiary) of Padang, 

 Sumatra. The largest species, the Indian N. chitala, attains 

 4 feet in length ; its flesh is said to be uncommonly rich and well 

 flavoured, but a strong prejudice exists against it, owing to the 

 Fish being supposed to live on human carcases. 



Fam. 10. Osteoglossidae. Margin of the upper jaw formed 

 by the praemaxillaries and the maxillaries, the latter the more 

 developed and firmly attached to the end of the former. Parietal 

 bones separating the supraoccipital from the frontals ; suboper- 

 culum much reduced, and entirely or partially concealed under 

 the praeoperculum. Basis cranii simple. Teeth in jaws, and on 

 pterygoid and hyoid bones ; no pharyngeal teeth. Head scale- 

 less, the thin skin confluent with the bones; body covered with 

 large bony scales, composed of pieces like mosaic. Ribs inserted 

 on the strong parapophyses ; epineurals, no epipleurals. Pectoral 

 fins low down. Post-temporal forked, the upper branch attached 

 to the epiotic, the lower to the squamosal ; post-clavicle present ; 

 scapular foramen in scapula ; pterygials well developed, only one 

 in contact with coracoid. Dorsal and anal fins originating behind 

 the ventrals ; latter with 5 or 6 rays. No oviducts, the eggs 

 falling into the abdominal cavity before exclusion (at least in 

 Heterotis, as observed by Budgett). 



This family is represented at the present day by five species, 

 referred to four genera ; thus characterised : 



Scleropages. Mouth large; vomer, palatines, pterygoids, and 



1 Journ. Linn. Soc. xxvii. 1900, p. 503. 



