Fishes of the Western North Atlantic 299 



each shoulder; its dorsal fins are confluent (usually more or less separated in cubensis)\ 

 its teeth average slightly fewer than in cubensis\ and its rostral cartilage is considerably 

 shorter relatively than is usual in cubensis (see Fig. 62). 



Description. Proportional dimensions in per cent of total length. Female, 216 mm, 

 and male, 230 mm (Harv. Mus. Comp. Zool., No. 36493), from off Jacksonville, 

 Florida. 



Disc: extreme breadth 43.5, 44.3; length 35.7, 38.2. 



Snout length: in front of orbits 7.9, 6.7; in front of mouth 8.8, 8.7. 



Orbits: horizontal diameter 4.4, 5.2; distance between 3.0, 3.5. 



Spiracles: length 2.3, 2.4; distance between 7.0, 7.0. 



Mouth: breadth 5.1, 5.6. 



Nostrils: distance between inner ends 3.9, 4.8. 



Gill openings: lengths, ist 1.3, 1.3; 3rd 1.3, 1.3; 5th 1.2, i.i ; distance between 

 inner ends, ist 1 1.3, i i.i ; 5th 7.6, 5.6. 



First dorsal fin: vertical height 1.4, 1.5; length of base 3.7, 4.8. 



Second dorsal fin: vertical height 1.6, 1.4; length of base 3.5, 4.8. 



Pelvics: anterior margin 9.3, 1 1.7. 



Distance: from tip of snout to center of cloaca 33.3, 36. i ; from center of cloaca 

 to ist dorsal 57.0, 51.8; to tip of tail 66.7, 63.9; from rear end of 2nd 

 dorsal base to tip of caudal 2.5, 2.6. 



Interspace between: ist and 2nd dorsals 0.0, 0.0. 



Disc about 1.2 times as wide as long, broadly rounded in front; tip of snout marked 

 by a low, blunt subtriangular projection; maximum anterior angle in front of spiracles 

 about 130-135°; anterior margins concave abreast of spiracles, more deeply so on adult 

 males than on females or on young; both outer and posterior corners broadly rounded; 

 posterior margins moderately and evenly convex, inner margins weakly so. Tail with 

 narrow lateral fold low down on each side along posterior two-fifths extending to tip; 

 its length to first dorsal about 1.4-1.7 times as great as distance from center of cloaca 

 to tip of snout and about 1.8-2.0 times as great to tip. 



Upper surface smooth on tip of snout and around rear corners of pectorals but 

 prickly elsewhere on disc and on tail, most densely so above eyes; orbit with two small 

 thorns on posterior margin on small specimens and up to 12 in a continuous row around 

 inner edge on adults; one larger thorn inward from inner end of spiracle; 2—3 on each 

 shoulder on young, 3—4 in a transverse row on adults, these being larger and more 

 conspicuous on females than on mature males and preceded on some by one thorn on 

 either side in advance of shoulder; midline of back with a continuous row of larger and 

 smaller thorns (varying considerably in number on specimens of the same size), about 

 45-70 from nuchal region back to about midlength of tail, followed rearward to first 

 dorsal by thorns less regularly arranged, often interrupted and usually not in exact mid- 

 line; an additional row of irregularly arranged smaller thorns on either side of the median 

 row from pectoral girdle rearward along anterior part of tail, succeeded by 1—3 irregular 

 rows to first dorsal and by smaller thorns or prickles to tip of tail; pelvics naked in both 



