PART 5 A MONOGRAPH OF THE EXISTING CRESTOIDS 271 



The anterolateral angles of the radials are just visible interradially. The IBr! are 

 very short, narrowing rapidly from the proximal to the distal edge, and widely sepa- 

 rated laterally; beneath them is a small narrow transverse cleft; their dorsal surface is 

 almost flat, but in the distal portion of the median line rises to a slight tubercle with the 

 IBr 2 (axillaries) which are pentagonal, somewhat broader than long, widening rapidly 

 from the proximal edge to the lateral angles; the distal sides are slightly concave, and 

 the proximal bonier slightly convex in the median line where it rises to a slight tubercle 

 with the IBri. 



The 10 arms are from 110 to 120 mm. long. The first brachials are wedge-shaped, 

 slightly longer on the outer than on the inner side, united interiorly for their basal half, 

 the free portions of their inner sides standing at right angles to the united basal por- 

 tions. The second brachials are irregularly quadrate with a slight posterior convexity 

 slightly incising the first brachials. The first syzygial pair (composed of the third and 

 fourth brachials) is oblong, not quite twice as broad as long. The following brachials 

 are wedge-shaped, about twice as broad as long, the succeeding gradually becoming more 

 and more nearly oblong, and quite oblong, not quite twice as broad as long, after about 

 the thirty -fifth or fortieth, that is, after about the end of the proximal third of the arm. 

 Distally the brachials gradually become more elongate, at the end of the arm being 

 twice as long as broad or even slightly longer. 



Syzygies occur between brachials 3+4, 9 + 10 and 14 + 15, and distally at intervals 

 of 3 muscular articulations. 



P, is about 14 mm. long, tapering evenly from the base to the slender and flagel- 

 late tip, and slightly compressed laterally; it is composed of 35 to 40 segments, all of 

 which are about as long as broad; the distal corners of the segments are somewhat 

 prominent, giving the pinnule a somewhat serrate dorsal profile, which becomes more 

 pronounced distally. P 2 is shorter than P 1( 10 mm. long, composed of about 20 seg- 

 ments, of which the first is not so long as broad, the second and third are about as long 

 as broad, and the following become progressively elongated, and very long and slender 

 distally; the pinnule is about as stout basally as PI. P 3 is 8 mm. long with 15 segments, 

 basally about as stout as the two preceding but tapering less gradually; the first seg- 

 ment is not so long as broad, the next two are about as long as broad, and the remainder 

 gradually become elongated and distally very long and slender; there is a large gonad 

 on the third or fourth to the eighth or ninth segments. The following pinnules to about 

 the thirteenth are similar, but gradually become shorter. The distal pinnules are 

 20 mm. long, very slender, composed of 25 to 30 segments, of which the first is very 

 short, the second is wedge-shaped, not quite so long as broad, the third is about as long 

 as, or slightly longer than, broad, and those following become progressively elongated. 



Localities. Albatross station 3698; Sagami Bay, Japan; Manazuru Light bearing 

 N. 8 W., 4.5 miles distant; 279 meters; temperature 18.33 C.; green mud, volcanic 

 ash, and sand; May 5, 1900 (1, U.S.N.M., 35960). 



Albatross station 5091 ; Uraga Straits, at the entrance to Tokyo Gulf (lat. 3504'10" 

 N., long. 13938'12" E.); Joga Shima Light bearing N. 15 W., 4.2 miles distant; 360 

 meters; bottom temperature 8.67 C.; green mud, coarse black sand, and pebbles; 

 October 26, 1906 (1, U.S.N.M, 35932). 



Albatross station 5092; Uraga Straits (lat. 3504'50" N., long. 13938'18" E.); 

 Joga Shima Light bearing N. 19 W., 3.5 miles distant; 128 meters; bottom temperature 



