A MONOGRAPH OF THE EXISTING CRINOIDS 521 



arm but is only about 8 mm. long and consists of only 17 or 18 segments. None of 

 the proximal pinnules are noticeably flagellate at the tip, as they are in the specimens 

 from Mabuag. The cirri are XX, 18-24, with evident sockets for about 10 more 

 cirri, which apparently have been very recently lost. Dr. Clark said that in this 

 specimen the lower pinnules are stouter and the coloration is more variegated and 

 much handsomer than in specimens from the Marshall Islands. In alcohol the blue 

 and yellow tints have been lost, and the colors are dull reddish purple and reddish 

 white. 



Dr. Clark said that the single specimen from the Great Barrier reef is adult, more 

 or less broken, but in fair condition, with arms 60-75 mm. long. It is of a deep 

 purple-red color. 



According to McNeill and Livingstone the specimen from Port Darwin is, in 

 alcohol, dusky brown; the arms are about 65 mm. long. 



Dr. H. L. Clark collected five young specimens at Darwin; 18 adults, large and 

 small, at Broome; and 1 adult at False Cape Bossut. He said that this many-armed 

 comatulid is common on the tropical coasts of Australia and its diversity of color and 

 of arm length make it a very perplexing species. He was not all at convinced that 

 several different species are not included under one specific name. On the other 

 hand, he said, the supposed distinction between gyges and protectus is based upon a 

 very variable character, and the line is hard to draw. His 24 specimens ranged from 

 a young one with only 19 arms from 20 to 25 mm. long and the cirri XV, 14-15, up to 

 fine adults with 45-51 arms 70 to 100 mm. long and with the cirri XXXVIII-XLVIII, 

 26-30. 



The specimens from the Hamburg Southwest Australian Expedition stations 14 

 and 22 are both small and immature. That from station 22 has 33 arms 55 mm. 

 long; P 2 is 12 mm. long. 



The specimen presumably from the vicinity of Perth has seven radials and is 

 described under the heading "Abnormal Specimen" (see p. 522). 



Dr. H. L. Clark said that the two specimens from Wooded Isle, Abrolhos Islands, 

 are light brown. The arms are about 100 mm. long, and their segments proximally 

 are so closely apposed to each other that the basal part of the arm is noticeably 

 smooth and regular. The cirri are XXX-XXXII, 25-30; one specimen shows 23 

 additional cirrus sockets. The cirri are less brown, grayer, than the calyx. In one 

 specimen there can be distinguished along the dorsal side of each fully developed 

 arm an inconspicuous longitudinal whitish line. 



The specimen from Siboga station 209 has 20 arms and agrees perfectly with 

 others at hand from the Marshall Islands. 



Hartlaub said that this species varies greatly in the length of the lower pinnules. 

 In the Gottingen specimen (from Queensland) these are strikingly small and fine, 

 while in the Hamburg specimen (from Port Denison) they are of considerable length, 

 and here they show, besides, the feature so characteristic of Antedon imparipinna, 

 that is, the lower pinnules on the outer arms are longer than those on the inner. But 

 both specimens agree in having the lower pinnules unusually slender, and this feature 

 differentiates them from imparipinna, in which P 2 is rather stout and stiff. In this 

 new species PI and P 2 are occasionally of the same length, and P a may even be longer 



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