230 Memoir Sears Foundation for Marine Research 



Nostrils: distance between inner ends 6.0, 6.2. 



Gill openings: length, ist 2.0, 1.5; 3rd 1.9, 1.8; 5th 1.2, 1.5; distance between 



inner ends, ist 13.9, 14.3; 5th 7.0, 7.8. 

 First dorsal fin: vertical height 3.0, 2.0; length of base 5.6, ^.■t,. 

 Second dorsal fin: vertical height 3.0, 2.0; length of base f,.^, 4.3. 

 Pelvics: anterior margin 12.2, ii.o. 

 Distance: from tip of snout to center of cloaca 39.2, 41.3 ; from center of cloaca 



to 1st dorsal 45.3, 44.0; to tip of tail 60.8, 58.7; from rear end of 2nd 



dorsal base to tip of caudal 2.9, 2.3. 

 Interspace between: ist and 2nd dorsals 1.2, 2.0. 



Disc about 1.2 — 1.3 times as broad as long, the maximum angle in front of spiracles 

 about 120°; anterior margins weakly convex from just posterior to tip of snout to 

 opposite orbits, thence gently concave between spiracles and outer corners, which are 

 broadly rounded; posterior margins and corners and inner margins all rounded. Axis 

 of greatest breadth about 68 "/o of distance back from tip of snout to axils of pectorals. 

 Tail with lateral fold low down on each side beginning abruptly posterior to axils of 

 pelvics by a distance about equal to space between spiracles and continuing almost to 

 extreme tip; width of fold about the same throughout its length; length of tail from 

 center of cloaca to origin of first dorsal fin i.i— 1.2 times as great as, its length to tip 

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



Four to six prominent thorns along anterior edge of orbit, none or one opposite 

 its inner central margin, and two to five along its posterior margin, the last opposite 

 spiracle; an additional thorn inward from this last one; a row of thorns over margins 

 of rostral process; prickles and small thorns present over anterior third of disc in 

 advance of nuchal region, extending along outer margin rearward about to axils of 

 pectorals; a triangular patch of about 15—17 thorns on shoulder region, 4 or 5 of which 

 extend along median line from nuchal to scapular region ; a naked area behind these 

 for a distance about equal to length of distance between spiracles on males (not on 

 females); band of 3—5 rows of thorns along median zone of back and tail from nuchal 

 region to first dorsal, the thorns rather regular on some specimens but irregular on 

 others, the lowermost row reaching nearly to tip of tail, the median row consisting of 

 about 45—53 thorns in most cases, large and small alternating on males but all of about 

 equal size on females; most of the thorns on tail with sharp points, directed rearward; 

 1—4 prominent thorns in space between dorsals; prickles on dorsal fins and caudal; 

 skin over eye naked. Males with a band of alar spines in one to three rows on outer 

 part of each pectoral, the longest row with 19 spines. Female of 302 mm with small 

 thorns on posterior part of pectorals and a few on pelvics. Lower surface naked except 

 for a small median patch of spines at extreme tip of snout, lacking on our specimens 

 of 232 mm and smaller. 



Snout in front of orbits 2.0—2.2 times as long as orbit, its length in front of mouth 

 about 1.7— 1.8 times as great as distance between exposed nostrils. Orbit about twice 



