54 



Glj'ptosternon Bleeker, IclithyologiaG Archlpelagi Indici Prodromus, 

 vol. I. Siluri, pp. 190, 204, 214. 



Eight species of this genus are known, all of which are natives of 

 the rivers of and the islands of Java and Sumatra. 



The genera Ictalurus, Amiurus^ Noturus, and Ilopladelus were con- 

 founded by Dr. Bleeker under the name of Pimelodus. The group 

 so framed was characterized by the presence of eight or nine rays in 

 the ventral fins ; the branchiostegal membrane, furnished with from 

 eight to twelve rays, and the presence of a natatory bladder. 



He has referred to it all the North American Ictaluri, and also the 

 Pimelodus CrancJiii of Griffith's English edition and translation of 

 the " Regne Animal" of Cuvier ; the Pimelodus cantonensis of Valen- 

 ciennes, and Pimelodus guttatus of Lacepede. The Pimelodus Cran- 

 cJiii is probably a true Ictalurus^ but as no description is given, and 

 the figure is of no value for specific details, and as the habitat is also 

 unknown, the species is uncertain. As the specimen is said to be 

 preserved in the British Museum, Dr. Gunther will probably describe 

 it in a recognizable manner. 



The Pimelodus cantonensis and Pimelodus guttatus do not appear to 

 belong to any of the North American genera, but as they have only 

 been established on Chinese figures, they also must be considered as 

 doubtful for the present. 



Subfamily Heptapterin^ Gill. 



Body very slender and elongated, subfusiform, with the skin 

 smooth. 



Head oblong, much depressed, oval above and laterally elongate, 

 conical, or cuneiform ; covered by a soft and smooth skin. 



Eyes moderate, subcentral or subanterior. 



Barbels, six ; two supramaxillary and four inframaxillary. 



Nostrils distant, valvular. 



Teeth on the jaws, acute and pluriserial ; none on the vomer or 

 palate. 



Branchiostegal membrane emarginated, with nine rays on each 

 side. 



Dorsal fin subquadrate, distant from the head. 



Anal fin oblong, commencing under the adipose fin, and far behind 

 the anus. 



Adipose fin commencing some distance behind the dorsal, very 

 long, low, and compressed, and united with the procurrent rudimen- 

 tary rays of the entire caudal. 



Pectoral fins rounded, with the first ray spinous. 



Ventrals under the anterior or middle part of the dorsal, sustained 

 by six rays. 



The single species of this section which is yet known, dilfers too 



