THE AMERICAN TETRAGONOPTERINAE. 



283 



second tooth of the inner series; five teeth in the inner series, their denticles 

 in a shallow crescent. Maxillary without teeth. Mandible with four gradu- 

 ated teeth arranged in a crescent, and foiu" small conical teeth on the side. 



Origin of dorsal exactly equidistant from tip of snout and base of caudal. 

 Base of anal very little more than distance from dorsal to adipose. Origin of 

 ventrals equidistant from tip of snout and tip of last anal ray, in advance of the 

 dorsal. 



The scales are mostly gone, a few below the dorsal have about eight divergent 

 striae. Scales about 6-34^?. 



A roundish, humeral spot above the 3rd-5th scale of the lateral Une, sur- 

 rounded by silvery, a dark cross shade behind the silver; a silvery band; no 

 caudal spot. 



39. AsTYANAX MARioNAE Eigeumanu. 

 Plate 62, fig. 2. 



Astrjanax marionne Eigenmann, Ann. Carnegie mus., 1911, 8, p. 175, pi. 7, fig. 3. 



Habitat. — Upper Paraguay Basin. 



Specimens examined. 



Catalogue Number of Size 



number specimens in mm. 



33.53 C. Type 1 54 



3354 C. Paratypes 4 16-51 



) 43-50 



3355 C. Paratypes 



Locality Collector 



6 miles from San Luiz de Caceres Haseman 



Corumba Haseman 



Head 3.5-3.75; depth 2.8-3.2; D. 11; A. 27 or 28; scales 7-35-5; eye 2.5; 

 interorbital 3. 



Slender, dorsal and anal profiles gently and equally curved. Ventral areas 

 rounded. Preventral area without a distinct median series of scales. Predorsal 

 area with about ten scales. 



Occipital process about one fifth of the space between its base and the 

 dorsal. Interorbital but slightly convex. Frontal fontanel but little shorter, 

 but much narrower than the parietal. Second suborbital leaving a narrow 

 naked margin. Maxillary slender, one half the length of the snout and eye. 

 Foiu- teeth in the front row of the premaxillary, five in the second row. Maxil- 

 lary with one small tooth. Mandible with four large teeth in front and several 

 abruptly minute ones in each dentary. 



Gill-rakers 8 -f-ll. 



