30 



SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I07 



crossing middle of side (too irregular to enumerate accurately), about 

 60 to 70, 64 ; vertical series of scales between tip of pectoral and base 

 of ventral 5 to 8, 5 ; modified scales in a series in front of dorsal fin 

 39 to 45, 45; ventral scutes 30 to 33, 31 ; gill rakers on lower limb 

 of first arch about 125 to 149 (enumerated in 6 specimens) ; vertebrae 

 45 to 47 (enumerated in 9 specimens). 



Relationship. — B. smithi is close to B. gunteri n. sp., which is its 

 counterpart in the Gulf of Mexico. The relationship of these two 

 species is shown in the account of the last-mentioned species. B. smithi 

 differs rather prominently from B. tyr annus, with which it was long 

 confused, as shown in the following comparison. As the proportions 

 and enumerations for tyrannus are based on 200 specimens or more, 

 the "usual" range can be stated, but that is not possible for smithi of 

 which only 18 specimens are at hand. 



tyrannus 



Scales moderately large, arranged in 

 fairly regular series, 41 to 55, usu- 

 ally 45 to 52, oblique series crossing 

 middle of side; scales on middle of 

 side with long, hairlike pectinations 

 in large examples (see fig. 8, B), 

 modified scales on back in front of 

 dorsal fin with long hairlike pec- 

 tinations in adults, 31 to 43, usu- 

 ally 33 to 39 in a series. 



Upper part of opercle with prominent 

 radiating striations. 



Head moderately large, 28 to 35, usu- 

 ally 31 to 34, average 32.2 percent 

 of standard length. 



Body moderately deep, the ventral out- 

 line anteriorly moderately convex, 

 usually only half the greatest depth 

 below a straight line extending 

 through lower margin of eye to 

 middle of base of caudal, its greatest 

 depth 30 to 39, usually 32 to 27, 

 average 34.2 percent of standard 

 length. 



Anal base rather short, 14 to 19, 

 usually 15 to 18, average 16.5 per- 

 cent of standard length. 



Caudal fin rather short, the lower 

 lobe about as long as head, 25 to 35, 

 usually 26 to 33, average 29.4 per- 

 cent of standard length, if measured 

 from middle of base of caudal. 



smithi 



Scales notably smaller and less regu- 

 larly placed, about 60 to 70 oblique 

 series crossing middle of side ; scales 

 on middle of side with notably 

 shorter and blunter pectinations in 

 large examples (see fig. 8, F) ; 

 modified scales on back in front of 

 dorsal fin with notably shorter and 

 blunter pectinations in adults, 39 to 

 45 in a series. 



Upper part of opercle with very feeble 

 striations, or none. 



Head smaller, 29 to 32, average 30.7 

 percent of standard length. 



Body rather deeper, the ventral outline 

 anteriorly more strongly convex, 

 more than half the greatest depth 

 below a straight line extending 

 through lower margin of eye to 

 middle of base of caudal, its greatest 

 depth 36 to 43, average 38.7 percent 

 of standard length. 



Anal base longer, 19 to 21, average 

 19.9 percent of standard length. 



Caudal fin longer, the lower lobe longer 

 than head, 32 to 37, average 33.8 

 percent of standard length, if mea- 

 sured as in tyrannus. 



