A MONOGRAPH OF THE EXISTING CRINOIDS 463 



that these fragments must belong to this species. They agree very closely with 

 the corresponding parts of the arms in a specimen at hand from Torres Strait. 



Professor Doderlein recorded 2 specimens from Thursday Island. A small 

 individual with a maximum arm length of 30 mm. in which 2 rays are in process of 

 adolescent autotomy does not exhibit the keels on the basal pinnule segments which 

 are so characteristic of large examples. The color in alcohol is pale yellowish. 



The 2 specimens from Mer are both small. According to H. L. Clark the cirri 

 are XX-XXI, 15-17. One has CO and the other 70 arms. In the specimen \vith 60 

 arms 4 rays are typical, but the fifth has the normal arrangement reversed, the inner 

 IIIBr series being 2 and the outer 4 (3 + 4). In the specimen with 70 arms only 

 2 rays show the typical arrangement, each of the other rays having an inner IIIBr 

 series 2 instead of 4 (3+4). 



The color of one of the individuals in life was described as having been black, 

 passing into olive at the tips of the arms; the distal half of each pinnule was chrome 

 yellow, passing through brown into the dull olive or black of the basal half; the 

 cirri were lemon yellow. The other was recorded as strikingly different, bewilder- 

 ingly variegated with shades of yellow, green, brown, blackish, and white, giving the 

 general impression of being bright yellow with black markings; the cirri were yellow 

 with 2 dusky dark bands. 



The specimen from the Great Barrier Reef is small, with 55 arms which are 

 about 100 mm. long. The cirri are XVIII, 15, short and stout, with the segments 

 subequal, the distal being only very slightly shorter than the proximal. There are 

 no dorsal processes. With the specimen is a color note, "deep purplish blue, the 

 pinnvdes purple with yellow tips; cirri lemon yellow." 



In Carpenter's original account of this species, which was based on 3 specimens 

 from Challenger station 186, he described the centrodorsal as being a moderately 

 thick circular disk hollowed in the center. 



The cirri are fairly stout, about XV, 15-20, with a few of the segments rather 

 longer than broad. 



There are 65-70 arms which are about 105 mm. long. The anterior arms are 

 long and slowly tapering, with 120-150 overlapping brachials which are shortly 

 triangular at the base, becoming quadrate about the middle and slightly elongated 

 near the tip. The posterior arms are shorter, with only 80-100 brachials, and taper 

 more rapidly. 



Pd is moderately stout and reaches 20 mm. in length. Pp on the inside of the 

 ray and Pi are nearly as long. But P^ is only half their length, and much more 

 slender, while P2 and P,, are the smallest on the arm. The terminal pinnules are 

 long and slender on the anterior arms, but shorter on the posterior ones. The basal 

 segments of the genital pinnules have sharp dorsal keels which arc less distinct in 

 the first few pinnules than in those immediately following. In the anterior arms 

 they are lost after about the fiftieth brachial, but they are traceable to near the end 

 of the posterior arms. The lowest pinnules have a well-marked comb which becomes 

 gradually smaller and is lost at about the fifteenth brachial. 



