Fishes of the Western North Atlantic 317 



First dorsal fin: vertical height 2.4, 2.4; length of base 4.4, 3.6. 



Second dorsal fin: vertical height 2.4, 1.8; length of base 3.7, 3.8. 



Pelvics: anterior margin 10.4, 9.0. 



Distance: from tip of snout to center of cloaca 37.3, 38.0; from center of cloaca 



to 1st dorsal 39.8, 41.2; to tip of tail 62.7, 62.0; from rear end of 2nd 



dorsal base to tip of caudal 3.7, 4.4. 

 Interspace between: ist and 2nd dorsals ii.i, 9.0. 



Disc about 1.3 times as broad as long, angular in front, tip of snout narrowly 

 rounded, maximum anterior angle in front of spiracles about 80 to 95°; anterior mar- 

 gins weakly concave close behind tip of snout, otherwise nearly straight in females but 

 noticeably concave again abreast of spiracles in mature males; outer corners narrowly 

 rounded, posterior corners more broadly so; posterior and inner margins weakly con- 

 vex. Axis of greatest breadth about 70 "/o of distance rearward from tip of snout toward 

 axils of pectorals. Tail noticeably slender, its lateral folds originating a little before 

 first dorsal fin, narrow anteriorly but a little wider from opposite origin of second 

 dorsal to tip of tail; its length from center of cloaca to origin of first dorsal about i.i 

 times as great as distance from center of cloaca to tip of snout, about 1.4— 1.5 times as 

 great to origin of second dorsal, and about 1.6— 1.7 times as great to tip. 



Half-grown specimens and larger with upper surface of disc (including skin over 

 eyes) thickly and evenly roughened with small prickles except on tip of snout, around 

 posterior margins of pectorals and over naked areas of varying extent on shoulder 

 region and rearward along either side of dorsal ridge. Adults of both sexes with 2-3 

 rows of small thorns along anterior part of rostral ridge; 1 1 — 12 somewhat larger thorns 

 around inner margin of orbit and 1—2 inward from inner end of spiracle; 2—4 on each 

 shoulder; a median row of about seven thorns flanked on either side by 4—5 lower 

 and more rounded tubercles, from nuchal region to pectoral girdle, these followed 

 after a short gap by 4—5 small thorns and then by 5—6 much larger ones to level of 

 axils of pectorals; the marginal regions abreast of eyes and spiracles thickly strewn 

 with small thorns on radiate bases grading down to prickles. Anterior part of tail with 

 5—7 irregular rows of thorns in adult females, these decreasing in number to 2—3 rows 

 nearing first dorsal; tails of adult males with about three irregular rows interspersed 

 with prickles; interspace between first and second dorsals with 1—2 rows of small 

 thorns. Pelvics smooth in both sexes, the dorsals with a few prickles. Small specimens 

 (100 mm) with upper surface of disc largely bare of prickles except along median zone 

 from shoulder girdle rearward; only 4—5 orbital thorns, 2—3 thorns along mid-dorsal 

 line between nuchal region and level of axils of pectorals, and 1—2 rows along tail. 

 Alar spines of sexually mature males in 4—5 rows. Lower surface smooth on both 

 disc and tail. 



Snout in front of orbit about i. 9-2.1 times as long as orbit, its length in front 

 of mouth about 2.4 times as great as distance between exposed nostrils. Orbit about 

 twice as long as width between orbits and about twice as long as spiracle. Distance 



