156 MEMOIRS OF THE CARNEGIE MUSEUM. 



27. Adontosternarchus sachsi (Peters). (Plate XXII, fig. 3.) 



Sternarchus sachsi Peters, Mb. Akad. Wiss. Berl., 1877, 473 (Apure); Sachs, Aus 

 den Llanos, Berlin, 1878, 153, fig. 279; Sachs, Unters. am Zitteraal, Leipzig, 

 1881, 13 (Apure); Eigenmann and Eigenmann, Proc. U. S. Nat. Mus., XIV, 

 1891, 62. 



Sternarchogiton sachsi Eigenmann and Ward, Proc. Wash. Acad. Sci., VII, 1905, 

 165 (Orinoco); Eigenmann, Repts. Princeton Univ. Exp. Patagonia, III, 

 1910, 448 (Orinoco). 



3199 C. M., six, 110-170 mm. San Joaquim, Sept. 5, 1909, Haseman. 



3200 C. M., fifty-one, 95-125 mm. Santarem, Dec. 12, 1909, Haseman. 



Head 8.25 to 10, greatest depth of the body 7.8 to 9.7 in the length to the 

 base of the caudal; anal rays, 154, 156, 168, 170, 176, 185. 



Fig. 17. Adontosternarchus sachsi (Peters). 



Snout 3.2 to 3.5 in the head; interorbital equal to or very slightly longer than 

 the snout; eye 2.75 to 3 in the snout, about 11 in the head. 



Body moderately elongate; head compressed; width of the body 3.25 to 3.75; 

 depth of the head 1.3 to 1.6 in the greatest body depth; anus about the length 

 of the snout behind the vertical from the eye; dorsal profile almost straight; ventral 

 profile rather regularly convex. 



Snout pointed, quite short and curved downward; mouth rather small; gape 

 moderate, bow-shaped and just reaching the vertical from the posterior nares; nares 

 jirominent, anterior about midway between the eye and tip of the snout, posterior 

 not quite touching the upper anterior margin of the eye; upper jaw included, lower 

 projecting very slightly and having a distinct V-shape notch in its center for the 

 reception of the upper jaw, its lateral edges flare upward; scales small, larger in 

 region of lateral line. 



Caudal, which is scaled for some distance out from the base, 1.8 to 2.3, pectorals 

 1 to 1.4 in the head; origin of the anal on or a little in front of the vertical from the 

 gill-opening. 



