Jordan and Everniann. — Fis/ics of North America. 131 



band of teeth 6 times as Avide as deep; palatine patches 1| diame- 

 ters of eye in width and length. (Eigeumann.) Surinam to Maranhao. 

 This form is regarded by Eigenmaun as a subspecies of the preceding. 

 As the two inhabit the same waters, phry(jiatus should be either a distinct 

 species or an extreme of individual variation, (phrygiatm, embroidered 

 in gold. ) 



Alius phnjgialHs, OuviER & A'alenciennes, xv, 7!), 184(1, Cayenne. 



Ariim 2>hriigi(ilHs, GiNTHEU, Cat., v, 15G, 18G4. 



Tuchistirus nigispinis phrygiaius, Eigenmann, S. A. Ncmatoguathi, 84, 1890. 



74. TACHYSURUS, Lacepede. 



197. T-iCHYSlKlS M CHALIS, (Giinther). 

 Head 4 ; depth 5. D. I, 7; A. 21. Teeth on palate large, granular; no 

 teeth on vomer; occipital process triangular, as long as broad, obtusely 

 keeled; groove of foutauello not reaching base of occipital process; pala- 

 tine teeth in 2 subtriaugular patches which sometimes meet in front; 

 maxillary barbels nearly reaching tiji of pectorals. Dorsal spine slightly 

 serrated on both edges Ij in head; adipose tin shorter than dorsal; pec- 

 toral spine as long as dorsal spine and stronger. Gniana. (Giinther.) 

 (nuchalis, pertaining to the nape.) 

 Arius nuchaUs, GfNTiiEn, Cat., v, 171, 1864, British Guiana. 

 Tachisunts wichalis, Eigenmann, S. A. Nematognathi, 86, 1890. 



198. TACHTSURl'S FISSl'S, (Cuviei- i- Valenciennes). 

 Head Sin length; maxillary barbels reaching almost to the middle of 

 the pectoral fin. Teeth ou the palate granular; no teeth on vomer; gill 

 membrane not forming a free margin across the isthmus. Head broader 

 than high. Soft portions of the head not pitted. Surinam. (Eigenmann.) 

 (Jisstis, split.) 



Ariiisfissus, Cuvier A A^alencienne.s, xv, 107, 1840, Cayenne. 



Arms Jisstis, GCnther, Cat., v, 172, 1804. 



Tachisurvs As'^us, Eigenmann, S. A. Neinatoirnathi, 88, 1890. 



AriKspmicticiilatiis, Cuviek & Valenciennes, xv, 108, 1840, Buenos Ayres. 



199. TACHYSURUS SPIXII, (Agassiz). 

 Head Sf to 4; depth 5 to 51. D. I, 7; A. 21. Palatine bands without 

 backward prolongation. Teeth on the palate, granular ; no teeth on 

 vomer; gill membrane not forming a free margin across the isthmus. 

 Head broader than high, more than 3 in the length. Axillary pore much 

 smaller than nasal opening. Pectoral spine reaching halfway to the 

 posterior third of the ventrals, or shorter; upper jaw projecting; poste- 

 rior margin of the eye about in the middle of the head. Occipital pro- 

 cess greatly narrowed behind, its width at tip not more than 1 diame- 

 ter of eye. Teeth on the palate large, granular, 20 or fewer, some 

 of the posterior ones usually much enlarged. Body compressed ; head 

 narrowed forward, fontanelle narrow ; not interrupted, continued as a 

 deep tapering groove to near base of occipital process. Maxillary barbels 

 variable, long. Brownish above, silvery below, sometimes dotted. Coast 

 of Guiana and Brazil, south to Santos; common. (Named for Jean Bap- 

 tiste Spix, of Munich, explorer in Brazil.) 



