eigenmann: the FRESHWATER FISHES OF BRITISH GUIANA 375 



Nineteen specimens, 41-81 mm. Crab Falls. (C. M. Cat. No. 1946a-e; 

 I. U. Cat. No. 12207.) 



Three specimens, 44-50 mm. Lama Stop-Off. (C. M. Cat. No. 1947a; 

 I. U. Cat. No. 12208.) 



One specimen, 50 mm. Amatuk. (C. M. Cat. No. 1948.) 



Two specimens, 58-87 mm. Creek below Potaro Landing. (C. M. Cat. No. 

 1949; I. U. Cat. No. 12209.) 



Seventy-two specimens, the largest 71 mm., most of them about 50 mm. 

 Konawaruk. (C. M. Cat. Nos. 1950a-?', and 2454 (figured) ; I. U. Cat, No. 12210.) 



Eighteen specimens, 96-115 mm. Kangaruma. (C. M. Cat. No. 1951a-e; 

 I. U. Cat. No. 12211.) 



Twenty-four specimens, 40-83 mm. Rockstone. (C. M. Cat. No. 1952a-e; 

 I. U. Cat, No. 12212.) 



Ninety-eight specimens, the largest 75 mm. Tumatumari. (C. M. Cat. No. 

 1953a-{; I. U. Cat. No. 12213.) 



One hundred and sixty-four specimens, the largest 70 mm. Wismar. (C. M. 

 Cat. No. 1954a-x; I. U. Cat. No. 12214.) 



Seven specimens, 45-52 mm. Warraputa. (C. M. Cat. No. 1955a-d; I. U. 

 Cat. No. 12215.) 



Five specimens, 55-71 mm. Label lost, either Botanic Gardens or mud-flats 

 below Wismar. (C. M. Cat. No. 1956a-c; I. U. Cat. No. 12216.) 



Eight specimens, 45-62 mm. Erukin. (C. M. Cat. No. 2206a-d; I. U. Cat. 

 No. 12362.) 



Head about 4; depth nearly 2 in the young, 1.4 in some of the largest; D. 11 

 or 12; A. 30-34, most frequently 32; scales 8-34 to 36-6 to 8. Eye .7 in the snout, 

 2.4-2.6 in the head, 1+ in the interorbital. 



Extremely deep and compressed, preventral surface bluntly keeled; in part 

 covered by median scales, in part by scales bent over the ridge; predorsal area 

 keeled, with a median series of about eight scales; ventral arch more pronounced 

 than the dorsal; anal base straight; predorsal profile arched, with a distinct de- 

 pression over the eyes; occipital process, as in all deep species, very long and narrow, 

 reaching one-third of the way to the dorsal, bordered by five scales on each side; 

 predorsal spine in old individuals more or less leaf-shaped, with entire margins, 

 in the young hastate, with a retrorse barb on each side; fontanel narrow, the parietal 

 continued as a deep groove on the occipital process. 



Second suborbital leaving but a very narrow naked margin in the adult; jaws 

 equal, the premaxillary with a short horizontal extent, meeting the maxillary at an 



