734 BULLETIN 10 0, UNITED STATES NATIONAL MUSEUM 



A gi'eat group known usually as tlie catfishes. They include over 

 a thousand species chiefly in the fresh waters of the globe, most of 

 which are found between the tropics. The few forms known from 

 the Philippines, excepting the Clariidae, are mostly marine. 



ANALYSIS OF FAMILIES 



o\ Dorsal spineless, very long ; adipose fin present or absent Clariidae 



al Dorsal with pungent spine. 



&\ Caudal pointed, confluent with so-called long second dorsal and anal ; no 



adipose fin Plotosidae 



b". Caudal forked, emarginate or truncate, without procurrent portion ; anal 

 short ; adipose fin present Tachysuridae 



Family CLARIIDAE 



Body elongate. Head broad, depressed. Eyes small. Mouth 

 transverse, terminal or subterminal. Barbels 4 pairs, as 1 nasal, 1 

 maxillary, and 2 mandibulars. Jaws with more or less united areas 

 of villiform teeth. Vomer with crescentic band of villiform teeth. 

 Front nostril in short tube each side behind upper lip. Hind nostril 

 more or less rounded slit behind each nasal barbel. Cranial roof 

 with occipital and frontal fontanel, occipital part prolonged. Cra- 

 nium with upper portions covered with osseous plates, lateral por- 

 tions often naked, forming casque covering accessory branchial 

 chamber of gill cavity containing accessory dendritic gills attached 

 to second and fourth branchial arches. Gill membranes shortly 

 united, deeply notched in middle, free from isthmus. Gill rakers 

 13 to 19. Branchiostegals 7 to 9. Air bladder small, bilobed, dis- 

 posed transversely and partially enclosed in bony sheath. Long 

 dorsal and anal entirely of soft rays, united with caudal or dorsal 

 shorter or followed by adipose fin. Pectoral with outer ray spinous. 

 Ventral rays 6. Paired fins sometimes rudimentary or absent. 



A large family of freshwater siluroids, more or less eellike in 

 appearance, some especially so or with the paired fins rudimentary 

 or absent. Most are furnished with an accessory dendritic breath- 

 ing organ within the branchial chamber which enables them to live 

 continuously for long periods of time on land. Some are known to 

 live in burrows during dry weather and crawl out at night in search 

 of food. 



ANALYSIS OF GENERA 



a\ No adipose fin on back ; dorsal long, nearly or quite reaches caudal or may 



be confluent Clarias 



al Adipose fin present behind rayed dorsal and like anal confluent with caudal. 



Heterobran chus 

 Genus CLARIAS Scopoli 



Clarias Gronow, Zoophylacii, p. 100, 1763. (Species nonbinomial.) (Type, 

 Clarias marpiis "Valencieuncs=/S/7Hr!/s iatrachus Linnaeus, designated by 

 Bleeker, Nederland. Tijdschr. Dlerk., vol. 1, p. 120, 1863.) 



