396 Memoir Sears Foundation for Marine Research 



Nostrils: distance between inner ends 5.8, 5.8. 



Gill opening lengths: ist2.3,2.4; 2nd 2.5, 2.6; 3rd 2.7, 2.8; 4th 2.7, 2.8; 5th 2.5, 



2.2. 



First dorsal fin: vertical height 9.1, 9.4; length of base ii.i, 10.8. 



Second dorsal fin: vertical height 2.5, 2.9; length of base 3.4, 3.4. 



Anal fin: vertical height 3.4, 3.2; length of base 4.6, 4.6. 



Caudal fin: upper margin 26.3, 26.6; lower anterior margin 1 1.7, 12.4. 



Pectoral fin: outer margin 15.5, 15.7; inner margin 5.9, 6.0; distal margin 12.2, 



12.4. 



Distance from snout to: ist dorsal 33.0, 32.2; 2nd dorsal 64.3, 62.6; upper 



caudal 73.7, 73.4; pectoral 23.5, 23.8; pelvics 47.O, 48.6; anal 60.7, 60.4. 



Interspace between: ist and 2nd dorsals 20.7, 20.6; 2nd dorsal and caudal 7.8, 



7.0; anal and caudal 7.6, 6.8. 



Distance from origin to origin of: pectoral and pelvics 25.2, 26.O; pelvics and anal 



13.4,13.8. 



Proportional dimensions in per cent of total length. Male, 831 mm., from Pacific 

 Panama (U.S. Nat. Mus., No. 79293). 



Trunk at origin of pectoral: breadth 1 1.2; height 12.0. 



Snout length in front of: outer nostrils 4. i ; mouth 7.5. 



Eye: horizontal diameter 1.6. 



Mouth: breadth 8.2; height 5.1. 



Nostrils: distance between inner ends 5.2. 



Gill opening lengths: 1st 3.1 ; 2nd 3.5; 3rd 3.4; 4th 3.4; 5th 3.0. 



First dorsal fin: vertical height 9.5; length of base 12.2. 



Second dorsal fin: vertical height 2.9; length of base 4.6. 



Anal fin: vertical height 3.8 ; length of base 4.7. 



Caudal fin: upper margin 24.7; lower anterior margin 1 1.9. 



Pectoral fin: outer margin 16.0; inner margin 5.8; distal margin 14.2. 



Distance from snout to: ist dorsal 33.3; 2nd dorsal 64.7; upper caudal 75.3; 



pectoral 23.6; pelvics 48.2; anal 62.5. 



Interspace between: ist and 2nd dorsals 21.9; 2nd dorsal and caudal 7.4; anal 



and caudal 7.1. 



Distance from origin to origin of: pectoral and pelvics 25.3; pelvics and anal 13.5. 



Height of trunk at ist dorsal about y^ its length to origin of caudal. Midline of back 

 smooth, with no trace of mid-dorsal ridge. Caudal peduncle about % as thick as high. 

 Upper precaudal pit strongly marked, semilunar to subangular, the lower similar but 

 less strongly marked. Dermal denticles overlapping so little that the skin is regularly or 

 partially exposed between them, their blades rising rather steeply and varying in size, only 

 a little broader than long, moderately arched longitudinally, with 3 ridges in small speci- 

 mens but 5 in larger, the median tooth considerably the largest; pedicels very short. 



