74 FIELD COLUMBIAN MUSEUM ZOOLOGY, VOL. III. 



Leptops olivaris (Rafinesque). 



One ^pecimen 5.80 inches long from the Rio Noavaco. 

 Large cat-fishes are reported to have been taken from the 

 Rio Conchos at Santa Rosalia. 



Rhamdia oaxacae, sp. nov. 



Type, No. 3717, F. C. M. Length, 5^ inches. 



Locality, Rio Quiotepec, Cuicatlan, Oaxaca, Mexico. 



Head 3|; depth 5^; D. i-6; A. 10; gill-rakers 3+7. Body 

 slender; head large, upper jaw slightly the longer; top of head 

 flat, narrow forward; eye small, 6^ in head; snout 2^ in head; 

 occipital process 4^ in head; fontanelle reaching middle of orbit; 

 profile from nostrils to origin of dorsal straight; maxillary bar- 

 bels reaching nearly to middle of base of adipose fin, slightly 

 shorter in largest specimens (6^ inches in length); mental barbel 

 reaching | distance to pectoral; post-mental to just past base 

 of pectoral; dorsal fin slightly higher than long, its base about 

 i| in head; dorsal spine weak, flexible, i^ in base of fin; 

 distance from tip of snout to dorsal fin -2\ in length of 

 body; adipose fin well developed, its origin at tips of dorsal 

 rays when the fin is deflexed; base of adipose fin a| to 3 in 

 length of body. Least depth of caudal peduncle i\ in head; 

 pectoral spine strong, with small teeth on its outer margin, the 

 larger two or three being near its tip; inner margin of pectoral 

 serrated, except the portion near the tip opposite the two or three 

 large teeth near tip on front; pectoral spine, 2| in head: ventrals 

 situated behind base of last dorsal ray; caudal forked, its lower 

 lobe broad and round, its upper pointed, with rounded tip. 

 Color uniform, dull olivaceous, slightly lighter on lower half of 

 body. A narrow dark band along lateral line. Dorsal fin with a 

 light cross band occupying the second fourth of fin from base. 

 No dark dots on body. 



This species differs from R. wagnerii in having a shorter head 

 and no black spots on the body. Cuicatlan. 



CATOSTOMID^. 

 Carpiodes tumidus Baird & Girard. 



Head 3^ in the length of the body; depth, 2| to 3!. Dorsal 

 rays 24 to 26; the anterior rays short; their tip, when fin is 

 depressed, reaching to about two-thirds the distance from base 



