PART 6 A MONOGRAPH OF THE EXISTING CRINOIDS 795 



penultimate segment, stout basally, tapering distally, comparatively straight in the 

 basal half but curved strongly downward at the tip. Tiie cirri are moderately com- 

 pressed; their component segments are practically oblong in lateral view, the distal 

 ventral ends of the basal ones being only very slightly prominent. 



The 5 arms are about 100 mm. long, and resemble those of P. semperi. The proxi- 

 mal portion of the arms shows a moderate development of articular tubercles. 



Notes. — The preceding description was drawn up from the type specimen dredged 

 by the Albatross off southwestern Japan at station 4934. 



Of the five specimens from the Philippines collected by the SiJo^o at station 95 the 

 best preserved has the cirri 27 mm. long with 17 to 19 (usually 18) segments. It agrees 

 well with a somewhat smaller indi\adual from the same region taken by the Albatross 

 at station 5173, which has the cirri 22 mm. long, with 14 to 16 segments, of the same 

 general proportions. The difference in size probably accounts for the difference in 

 the length of the cirri and in the number of segments. Three of the other four speci- 

 mens taken by the Siboga are smaller; one of them has the cirri 15 mm. long with 

 14 to 15 segments. 



[Notes by A.M.C] Gisl6n (1927) has given notes on two specimens taken by Dr. 

 Mortensen, one from off Kiu-Shiu and the other from the Sagami Sea. The former is 

 young with XXX cirri, 6 to 10.5 mm. long with 12 to 15 segments. The longest seg- 

 ments are up to four and a half times as long as wide and the penultimate is a little 

 longer than wide, without an opposing spine. The five arms are 60 mm. long and the 

 proximal brachials are 1 .0 mm. wide. The distal intersyzygial interval is four muscular 

 articulations. Pi and Pj (Pi and Pa according to our reckoning, see p. 786) are lacking 

 and the first pinnule is on Br; to the right in four cases out of five. This Pa (i.e. Pj) 

 Gisl6n says has about 25 segments and is 5.5 mm. long. Pj (Pb) on brachial 6 is 5.7 

 mm. long, with 25 segments, of which the distal ones are flattened, and most of them 

 are short, the longest segments being half again as long as their median widths. P3 

 (Pc) also has 25 segments; it is 6.7 mm. long. Pc (P4) has 23 segments, 7 mm. long. 

 The distal pinnules have 14 segments, 6.5 mm. long, all but the first two segments 

 being very slender, five times as long as \vide and shghtly thickened and spiny at the 

 ends. The disk is large, extending to brachial six or seven; it is naked or with minute 

 granules in the sldn. 



The specimen from the Sagami Sea has about L cirri, with 11 to 18 segments 

 and 5.5 to 16 mm. long. The longest segment is three times as long as broad. The 

 five arms are 90 mm. long and smooth. The distal intersyzj-gial interval is four to 

 six muscular articulations. Pa (i.e. Pj) is to the right on the fifth brachial in each case 

 and has 21 segments, 6.7 mm. long. The third segment is squarish, the fourth is half 

 again as long as broad. P5 (P3) is broken and has a small gonad. Po (P4) has 26 

 segments and is 12 mm. long. The distal pinnules have over 22 segments, about 15.5 mm. 

 long, with the fourth segment three times as long as broad and the distal segments sLx 

 to eight times as long as broad. The disk is somewhat incised, 7 to 1 1 mm. in diameter, 

 while the anal cone is 3.5 mm. high. 



Two loose arms from another specimen measure about 115 mm. in length. 



Of the five Siboga specimens from station 95, the best has the arm ^vidthat the 



first syzygy about 2.3 mm. and the length from the first brachial to 9 + 10 is 11.0 mm.; 



however, the second syzygy is very variable in position: of the four arms remaining 



beyond the first syzygy one has the second at 7 + 8, another at 9 + 10, the third at 10+11, 



530-622—67 52 



