A MONOGRAPH OF THE EXISTING CRINOIDS 



501 



than the others. Of the lowest pinnules P 2 is much larger than the others. P 3 is 

 the next largest. From P 3 the length of the pinnules rapidly decreases. The color 

 is blackish brown. 



In 1849 Professor Muller redescribcd this species under the name of Comatula 

 (Alecto) palmata, listing specimens from India, the Red Sea, and Zamboanga ("Sam- 

 buangam"). In the redescription the number of arms is given as 35-45. The latter 

 number is evidently taken from the specimen from Zamboanga in the Paris Museum 

 (see page 483). The radials are very short. All the axillaries are so articulated with 

 the preceding ossicles that they can be rocked toward the right and left. The 

 brachials are cylindrical, not wedge-shaped. The covering of the disk is without 

 plates, soft when wet but when dried rough to the touch because of being filled with 

 spicides. The anal tube is long and slender and is near the central mouth. The 

 expanse is nearly a foot (which would give an arm length of about 150 mm.). There 

 is no evidence that any of these additions to the original description were taken from 

 the specimens from the Red Sea. 



The specimen from India in the Indian Museum has 30 arms. 



The five specimens from ?India are small and medium sized. 



The 22 specimens from the Ceylon Pearl Oyster Fisheries investigations, of which 

 12 were from station II, were considered by Chadwick as representing a new species, 

 which he called Antedon okelli and described as follows: The centrodorsal is a moder- 

 ately thick roughly circular disk with a flat or very slightly convex dorsal surface 

 and sloping sides. The cirri are XX-XXV, 25-28. The more distal cirrus segments 

 are laterally compressed and carinate, and the penultimate bears an opposing spine. 

 The radials are distinctly visible. The IBr, are broad, well rounded, and form a 

 tubercular elevation in their median line of junction with the IBr 2 (axillaries), which 

 are broadly pentagonal and about half again as long as the IBr r . The IIBr and IIIBr 

 series are 2. The IIIBr series are borne upon the outer face of the IIBr axillaries of 

 one or both sides of the postradial series, generally the latter. Synarthrial tubercles 

 occur on both the IIBr and IIIBr series. The postradial series have slight marginal 

 projections. Arms 26-30, about 50 mm. long and consisting of about 120 brachials 

 of which the first seven or eight are moderately thick disks. These are followed by 

 rather more than 20 triangular brachials, and these again by wedge-shaped ones, 

 which become longer in proportion to their width as the tip of the arm is approached. 

 Syzygies occur between brachials 3+4, 14+15 or 15 + 16, 22+23 or 23+24, and 

 distally at intervals of 8 or 9 muscular articulations. 



Pj is composed of 18-20 segments, of which only a few of the more distal ones 

 are longer than broad. P a is smaller and slenderer and composed of 16 or 17 seg- 

 ments. P 2 is considerably stouter and longer than P, and is composed of 20-22, or 

 even 24, segments, which diminish in size more gradually. P b has 19 or 20 segments 

 but in all other respects is precisely like P 2 . P 3 and P c are smaller than P t and P a , 

 and composed of 14-16 segments. The basal segments of all these pinnules and of 

 the pinnules of the three or four succeeding pairs are distinctly carinate, the latter 

 especially so. The corresponding pinnules on the inner arms of the postradial series 

 are a little smaller and have slightly fewer segments. The disk is 10 mm. in diameter 

 and is deeply incised. SaccuH are abundant on the pinnules, less so on the disk. 

 The color in alcohol of the specimens from station I is creamy white, mottled and 



