1903.] NATURAL SCIENCES OF PHILADELPHIA. 503 



It is distinguished Ijy the obhque dark bar on the caudal, less distinct 

 than the rows of spots on the dorsal which toward the tip of the fin 

 are also partially resolved into bars. 



27. Cochliodon cochliodon (Kner). 



Two specimens (No. 211). 230 and 300 mm. Arroyo Trementina. 

 Caught in a fish trap. One specimen (No. 111). Matto Grosso? 



28. Pterygophliclitliys anisitsi sp. nov. Maimingu(>. 



Type No. 9,873. 42 cm. (46.) Co-types 9,874 and 9,875. Two 

 specimens (No. 46). 40-42 cm. Called La Aleja in Spanish and 

 Maimingue by the natives. Laguna of the Rio Paraguay at Asuncion. 

 Caught with seine; very abundant. 



Form slender; depth under dorsal 1^ in the width. Caudal pedmicle 

 slightly compressed. Head depressed, length 1^ in wddth, depth 1^ 

 in length. An occipital ridge. Occipital process narrow, the sides al- 

 most parallel, bordered by three nuchal plates. All dorsal and lateral 

 scutes carinate,' each carina with short spines. Tip of snout granular. 

 Thorax and abdomen entirely granulose. 



Eye 4^-5 in snout, 4-4 J in interorbital, 6-7 in head. Preopercle 

 erectile. 



Base of dorsal longer than distance from dorsal to base of caudal. 

 Distance from the dorsal to the adipose contained in the length of the 

 dorsal lf-2^ times. Distance of dorsal spines from snout 2h times in 

 length, the spine once in the head. The tips of the last dorsal rays 

 reach slightly more than ^ distance to adipose spine. 



Adipose spine hooked, compressed, covered with short spines, espe- 

 cially the curved end. 



Caudal obliciue, not emarginate; outer rays heavy, the dorsal one 

 somewhat compressed, not produced beyond the other caudal rays. 

 Height of anal H in head, ^'entrals equal length of head. Pectoral 

 spine reaching half the length of the ventrals. 



.Body dark, almost black, covered on the sides and belly with lighter 

 vermiculations. Passing caudad the vermiculations of the sides are 

 gradually replaced by spots. Back of the dorsal one spot on each 

 plate, so that the caudal peduncle has several longitudinal rows of 

 moderately large spots. The head with the same dark ground color 

 both above and below, uniformly covered with small light-colored 

 spots, those on the posterior part of the head larger and gradually 

 passing into the vermiculations of the sides. 



The interradial membrane of the dorsal, caudal, ventrals and pec- 

 torals dark, obscurely spotted, but in the darker individuals entirelj' 

 black. Anal membrane dusky with obscure spots. The rays of all 



