1  ^ '* tun 



Pi j/f.ato c/ia;/^ i0o>ii6 





« c/eo'de ji^"^ '**^^ 





ft. btucei uF S3il 



FiQUBE 5. — Swimbladders from four species of western Atlantic Argentina. See text for explanation. 



3b. Gill rakers on lower arm of first arch 5-10; jaw relatively small, snout to max- 

 illary tip distance usually more than 5 in head 5. 



4a. Head 3.0 (2.7-3.1) in standard length; eye 11.5 (10.5-12.7) in standard length; 



vertebrae 44 (43-45) ; lateral Une scales 47 (45-48) A. aliceae p. 19. 



4b. Head 3.5 (3.2-3.7) in standard length; eye 14.3 (12.7-16.4) in standard length; 



vertebrae 48 (47-50) ; lateral line scales 49 (48-51) A. sialic p. 22. 



5a. Gill rakers on lower arm of first arch 9 (8-10) A. elongata. 



5b. Gill rakers on lower arm of first arch 5-7 6. 



6a. Pectoral fin rays 13-14 A. australiae. 



18 



U.S. FISH AND WILDLIFE SERVICE 



