SOUTH AMERICAN NEMATOGNATHI. 173 



name clarias to the American form;' he probably copied 

 his synonymy. 



Cuvier and Valenciennes restrict the name clarias to 

 the Nile species, and propose the name blochii for the 

 American form. 



Miiller and Troschel first identified this species with 

 Arius albicans Valenciennes; they were followed by 

 Giinther in his Catalogue; and Steindachner in Siiss- 

 wasserfische siidostl. Bras. iv. Bleeker next supposes he 

 has a new species from Surinam allied to maculatus, and 

 names it macronema. 



Liitken next gives the differences between what he 

 supposes are albicans and clarias. As Dr. Giinther has 

 shown (Annals and Mag. Nat. Hist. 1880, 10), his albi- 

 cans was not Arius albicans Valenciennes. Liitken also 

 described a new species, pantherinus, from Venezuela, 

 and argues that the northern and southern forms are 

 distinct; he did not have specimens from the Amazon. 



Dr. Steindachner (Fisch - Fauna des Magdalenen 

 Stromes, 15) says that this species (clarias) is equally 

 abundant in the Magdalen River, the Orinoco, the 

 Amazon and the Rio Plata. He identifies albicans, 

 pantherinus and macronema with clarias. He has ex- 

 amined thirty-six specimens from the Rio Magdalena 

 which are all unspotted and have no teeth on the vomer, 

 and frequently the pterygoid teeth are absent; the only 

 constant character being the black spot at the base of 

 the dorsal spine. The specimens described by Kner 

 belong to the variety pantherinus. " Mit Riicksicht auf 

 das Langenverhaltniss der Fettflosse zur Dorsal und 

 Anal;" konnte diese Art " wieder in drei kiinstliche 

 Arten zersplittert werden." But later (page 61) in the 

 same paper, in a note, Dr. Steindachner states that since 

 the above was written he has received a specimen of 

 the albicans Liitken (not of Valenciennes), and that it is 



