89. STYGOGENES. 223 



tnil fins inserted just below the extremity of the pectoi-al, in the 

 vertical from the origin of the dorsal. Brown, dotted with black. 

 Andes of Western Ecuador. 



ft-d. From Mr. Fraser's Collection. 



89. STYGOGENES. 



Adipose fin short (with or without a spine) ; dorsal and anal short ; 

 the outer fin-rays somewhat thickened and rough. Teeth small, 

 slightly curved, notched at the apex, forming a narrow band in each 

 jaw ; palate toothless ; cleft of the mouth of moderate ^ndth, with 

 a maxillaiy barbel on each side ; a short broad flap on each side 

 between the nostrils ; lower lip very broad, pendent. Eyes small, 

 covered -with transparent skin. Head covered with soft sldn. Gill- 

 openings not extending downwards to the throat, separated by a 

 broad isthmus. Ventrals six-rayed, inserted below the dorsal. 



I establish tliis genus on a few very small fishes collected by the late 

 Madame Pfeift'er, and e\'idently very similar to the Fimelodus ciicloinim 

 of Humboldt. Indeed it is possible that they belong to that species, 

 which is so much coveted by zoologists, and the historj' of which is 

 still vefled in obsciuity. The descriptions by Humboldt are extremely 

 vague, and want the precision and detail requisite for the detennina- 

 tion of species ; and the figures illustrating them are below mediocrity, 

 convejdng little more than the general size and shape. Therefore, 

 when Valenciennes (xv. p. 326) extols the exactness of the figures 

 and descriptions of the fishes discovered by Humboldt, we must 

 consider it as a tribute to the " tendre ami tie que M. de Humboldt 

 a pour moi," &'c., rather than as consistent with fact. 



The most important difference between oirr specimens and the 

 Fiinehdus Cjidopum is in the structitre of the adii^ose fin, which is 

 supported by a small, stift', rough spine in our specimens, as in Hij- 

 postomus. Xo such spine is visible in the figure given by Humboldt. 

 But I would not aifirm that this is really a specific difference, as it 

 may have been overlooked by him. In other respects the fishes 

 agree, as far as we can judge from the monstrous figure. 



Madame Pfeiffer was not verj- accurate with regard to the localities 

 whence she obtained the species which she collected. Thus, our 

 specimens are marked as being from the Azores ; of course it is much 

 more probable that she obtained them during her travels in the 

 Andes ; perhaps she had some knowledge of the celebrated fish of 

 Ihimboldt, and inquired for it. 



It remains doubtful, therefore, whether our specimens are identical 

 with I'i)ii('JodHs cijclopum or not. The error of describing them as 

 distinct Avill be less than that of confounding them. If they be dis- 

 tinct, we should consider tlie new species as the type of the genus. 



1. Stygogenes humboldtii. 

 B. 4. D. 6-1. A. (i. C. 13. P. 8. V. C. 



In general form very similar to Anjc^. Tlu' head is as broad as 



