A MONOGRAPH OF THE EXISTING CRINOIDS 211 



three IIIBr series, all on a single postradial series, two 4(3+4) following the IIBr 

 2 series, and one 2, developed internally. P D (or PO is 9 mm. long with 21-22 seg- 

 ments, very stout basally but tapering evenly and becoming flagellate distally. P a is 

 similar but is somewhat smaller. The following pinnules are small and weak. 



In a specimen from the Danish Expedition to the Kei Islands station 19 the cirri 

 are large and stout, XXV, 35-36, 35 mm. long. The longest segments are about 

 one-third again as broad as long, or on some cirri nearly or even quite as long as broad. 

 Dorsal processes begin to appear on from the eighth to the tenth segment, and after 

 five or six become long and conspicuous triangular dorsal spines arising from the 

 entire dorsal surface of the segment which are either erect or directed distally; fre- 

 quently the tip of the spine is notched. The 47 arms are 150 mm. long. Of the 

 10 IIBr series present 7 are 4(3+4), one is 2, and 2 are 4, the two outer elements not 

 being united by syzygy. On two postradial series the IIIBr series are 4(3+4) exter- 

 nally and 2 internally. On two other postradial series three of the IIIBr series are 

 4(3+4), one of the two internally developed being 2. On the fifth postradial series 

 all the IIIBr series are 4 (3 + 4) . The I VBr series are all 4 (3 + 4) , and all are developed 

 on the inner portion of a postradial series, next the midradial line. 



P D is 22 mm. long, with 40 segments, of which the first is about twice as broad as 

 long, the second and third are slightly broader than long, and the remainder are about 

 as long as broad. The pinnule is moderately stout at the base but tapers in the 

 proximal third and in the outer half is slender and flagellate. The second-fourth 

 segments have a low well-rounded inconspicuous keel in the middle of the dorsal side. 

 P P is 23 mm. long, with 40 segments, in some cases resembling P D but usually somewhat 

 stouter, and sometimes considerably stouter. The first five to eight segments have 

 an obscure median elevation on the dorsal side and the second-eighth have the outer 

 edge (toward the arm tip) produced into a thin narrow keel. PI is 15-17 mm. long 

 with 31 segments, and resembles the preceding pinnules but is slenderer; the outer 

 border of the second-eighth segments is produced into a narrow knifelike carination. 

 P 2 is 11-12 mm. long, considerably slenderer than PI and is composed of 26 segments, 

 of which the outermost are about twice as long as broad. The second-sixth have a 

 more conspicuous carination of the outer edge than the corresponding segments of 

 the preceding pinnules. P 3 is 8 mm. long, with 19 segments, and is considerably 

 slenderer than P 2 . As in P 2 the second-sixth segments are very strongly carinate. 

 The following pinnules are smaller and shorter, with the third-sixth segments strongly 

 carinate. This carination of the earlier pinnule segments remains conspicuous until 

 about the middle of the arm and is indicated even on the second and third segments 

 of the terminal pinnules. 



Of the other specimens from the Danish Expedition to the Kei Islands station 

 19 one has 47 arms 140 mm. long and the cirri 40 mm. long with 35 segments, and 

 another has 37 arms 140 mm. long. 



In one of the specimens from Amboina there are 47 arms 140 mm. long, and the 

 longest cirri are 50 mm. long, with 37-43 segments. The other specimen from 

 Amboina has 42 arms 125 mm. long. 



The specimen collected by the Willebrord Snellius at Amboina is a fine example 

 with 55 arms 150 mm. long. P c and P P have 38-40 segments. 



