3 2 o Memoir Sears Foundation for Marine Research 



Distinctive Characters. See Relationships for differences between mediocris and chry- 

 sochloris (p. 322). From species oi Alosa and other Pomolobus species, excepting chryso- 

 chloris, it is marked by the noticeably smaller number of gill rakers. 



Description. Proportional dimensions in per cent of standard length, and counts, 

 based on 43 specimens, 82— 354 mm SL. 



Figure 79. Pomolobus mediocris, 309 mm TL, Brunswick, Georgia, USNM 1 181 56. Drawn by Nancy D. 

 Patton. 



Body, depth 26.7-32.8. 

 Caudal peduncle: depth 9.7—12. 

 Head: length 24.5—29.6. 

 Snout: length 5.9-7.5. 

 Eye: diameter 4.9-7.1. 

 Interorbital: width 3.9-5.4. 

 Maxillary: length 10.4— 13.4. 

 Pelvic fin: length 10.6— 12.4. 

 Pectoral fin: length 17—21. 



Scales: 48—57. 



Ventral scutes: 33-38, most frequently 

 36 or 37. 



Gill rakers: on lower limb 18—23, usually 

 20 or 21. 



Fin rays: dorsal 15—20, most frequently 

 17 or 18; anal 19—23, most fre- 

 quently 20 or 2 1 ; pectoral 1 5 or 16. 



Vertebrae: 54 or i,(^ (2 specimens). 



Body moderately slender, well compressed, its greatest thickness notably less than 

 half of its depth, its depth rather greater in large than in small specimens, usually 

 exceeding length of head, 3.0—3.75 in SL. 



Scales only moderately adherent, with definitely crenulate membranous margin, 

 preceded by longitudinal striae; about 16 longitudinal rows of scales on body between 

 base of pelvic and anterior dorsal rays. Ventral scutes moderately developed, 19—23 

 (usually 20—22) in front of pelvic fins, 12-17 (usually 13—16) behind them. 



Head 3.4-4.1 in SL. Snout 3.7-5.0 in head. Eye 3.9—5.3. Interorbital 5.5— 

 7.0. Cheek generally about as deep as long (Fig. 76 b). Mouth oblique. Upper jaw 

 with a definite median notch. Lower jaw projecting strongly and extending into dorsal 

 profile of head (Fig. 76 b), its upper margin within the mouth rising gradually, not 

 forming an angle (Fig. 76 b). Maxillary broad, its width somewhat more than half 

 of length of snout, rounded posteriorly, reaching about to vertical from posterior 



