88 CLASS XIV. 



Sp. Saccobranchus fossilis, Silurus fos&ilis BLOCK, Ichlh. Tab. 370, fig. 2 ; 

 H. BUCHANAN, Fishes of the Ganges, PL 37, fig. 46 ; in Bengal. The sin- 

 gular, elongated air-sacs receive a branch from the branchial arteries, and 

 their veins go to the aorta ; consequently they are respiratory organs sup- 

 plementary to the gills ; see J. TAYLOK, Edinburgh Journal of Science, 

 v. 1834. 



Clarias GnONOV., VALENC., Macropteronotus LACEP., Hetero- 

 branchus GEOFFR. Head mailed. Body naked. Teeth very thin, 

 crowded in both jaws and in vomer. Branchiostegous membrane, 

 with 9 15 rays. Dorsal fins two, the second adipose, or a single, 

 long fin, supported by rays. Cirri eight or six. Arborescent 

 appendages, adhering to the third and fourth branchial arch. 



a) Dorsal fin single; with 8 cirri. Clarias GRONOV., VALENC. 



Sp. Clarias ffasselquisti VALENC., Silurus anguillaris L. (excl. synon.), 

 SONNINI Voyage en Egypte, PI. 22, fig. 2, Cuv. R. Ani., 6d. ill., Poiss. PI. 

 101, fig. 2 (the branchial appendages fig. 2a, 2b.) Charmuth HASSELQUIST, 

 It. Palastin., p. 371, Yarmouth SONNINI ; in the Nile ; Clarias marpus 

 VALENC., GRONOV. Zoophylac. Tab. 8, fig. 35, &c. 



b) Dorsal fins 2 ; with 6 cirri, ffeterobranchus VALENC. 



Sp. ffeterobranchus Geoffroyi VALENC., ffeterobranchus bidorsalis GEOFFR., &c. 



Plotosus LACEP. Head and body naked. Teeth conical, crowded 

 in maxilloe, globose or rotundate in vomer. Branchiostegous mem- 

 brane with ten or eleven rays. Dorsal fins two, supported by rays, 

 second elongate, confluent at the acuminate apex of tail with the 

 caudal and anal. First ray of dorsal fin and of pectoral fins 

 dentate. 



Sp. Plotosus lineatus VALENC., LACEP. Poiss. v. PI. 3, fig. 2, Platystacus an- 

 guillaris BLOCH Ichth. Tab. 373, figs, i, 2, Syst. Ichth. Tab. 74 ? Plotosus 

 albilabris VALENC., GUERIN Iconogr., Poiss. PI. 53, fig. 3, &c. 



Malapterurus LACEP. Head and body naked. Teeth small, 

 congested into a cres.centic row in each maxilla. Branchiostegous 

 membrane with 7 8 rays. Dorsal fin single, adipose, remote. 

 Pectoral fin unarmed. 



Ailia GRAY, VALENC. Ventral fins approaching the pectoral, 

 subthoracic. Anal fin long. Body compressed. Eight long cirri. 



Sp. Malapterus (sic) Ailia Bengalensis GRAY, Indian Zoology, PI. 85, fig. 2. 



Malapterurus LAC., VALENC. Ventral fins remote. Anal fin 

 short. Body round. Six short cirri. 



