A MONOGRAPH OF THE EXISTING CRINOIDS 139 



History. — This species was first described in 1911 from five specimens collected 

 by the Albatross in the Philippines in 1909, four of them at station 5356 and a small 

 individual at station 5414. 



In 1918 three additional specimens were recorded by the author from two Siboga 

 stations. 



CATOPTOMETBA HARTLAUBI (A. H. Clark) 



Plate 8, Figure 28; Plate 9, Figure 34; Plate 11, Figures 43, 44 



(See also vol. 1, pt. 1, fig. 251 (centrodorsal) , p. 253; fig. 334 (cirrus), p. 283; fig. 467 (centrodorsal) , 

 p. 359; pt. 2, figs. 32, 33 (radial pentagon), p. 20.] 



Antedon hartlaubi A. H. Clark, Proc. U. S. Nat. Mus., vol. 33, 1907, p. 72 (description; Albatross 

 station 4934); vol. 34, 1908, p. 475 (listed). 



Zygometra koehleri A. H. Clark, Smithsonian Misc. Coll., vol. 50, 1907, p. 339 (description; Albatross 

 station 3717), p. 348 (listed); Proc. U. S. Nat. Mus., vol. 34, 1908, p. 271 (relation to species of 

 Eudiocrinus) , p. 542 (listed); Unstalked crinoids of the <Siboya-Exped., 1918, p. 63, footnote 

 (synonym of C. hartlaubi). 



Zygometra hartlaubi A. H. Clark, Smithsonian Misc. Coll., vol. 50, pt. 3, 1907, p. 348 (listed) ; Proc. 

 U. S. Nat. Mus., vol. 34, 1908, p. 271 (relation to species of Eudiocrinus), p. 276, figs. 6, 7 

 (centrodorsal and radial articular faces) . 



Catoptometra hartlaubi A. H. Clark, Proc. U. S. Nat. Mus., vol. 34, 1908, p. 317 (listed); vol. 39, 

 1911, p. 540 (compared with C. ophiura); Crinoids of the Indian Ocean, 1912, p. 21 (attains 

 greatest depth of any species of the family), p. 106 (synonymy; habitat); Journ. Washington 

 Acad. Sci., vol. 5, 1915, p. 214 (southern Japanese species; range and its significance); Amer. 

 Journ. Sci., vol. 40, 1915, p. 62 (listed); Unstalked crinoids of the Siboga-Exped., 1918, p. 63 

 (in key; range). — Gislen, Nova Acta Reg. Soc. Sci. Upsaliensis, ser. 4, vol. 5, No. 6, 1922, p. 4 

 (245 m.), p. 6 (Kiu Shiu and Goto Islands), p. 64 (Bock's station 5; detailed notes), p. 180 

 (listed), figs. 48-51, p. 70— Gislen, Vid. Medd. Dansk Naturh. Foren., vol. 83, 1927, p. 2 

 (Mortensen's station 5; 243 m.), p. 20 (station 5; notes), p. 22 (compared with C. rubroflava), 

 p. 68 (listed); Kungl. Fysiogr. Sallsk. Handl., new ser., vol. 45, No. 11, 1934, pp. 21, 29. 



Antedon hartlaubi S. and R. M. Pace, Zool. Rec, 1907, V. Echinoderma, Dec. 1908, p. 38 Ech. 



Catoptometra koehleri A. H. Clark, Proc. U. S. Nat. Mus., vol. 34, 1908, p. 317 (listed); Crinoids of 

 the Indian Ocean, 1912, p. 107 (habitat). 



Diagnostic features. — The arms are 20-23 (usually 20) in number and 70 to 120 

 mm. in length; the IIBr series are 4(3+4); the cirri are composed of 14-17 (usually 

 14-15) segments of which the fourth and following are all about twice as long as broad. 



This species is easily distinguished from C. rubroflava, which occurs in the same 

 region, by the greater number of arms and by the longer and more slender cirri, 

 which are recurved only in the distal half and are composed of much longer segments. 

 From C. ophiura it is distinguished by the more slender and less regularly recurved 

 cirri, which have longer distal segments, by the prominently everted spinous distal 

 ends of the elements of the division series and first two brachials, and by the papillose 

 or finely spinous dorsal pole of the centrodorsal. 



Description. — The centrodorsal is a thick disk, with the large bare polar area flat 

 or very slightly concave and beset with well separated small spines. The cirrus sockets 

 are arranged in 2 crowded rows of about 15 each. 



The cirri are XXX, 15, 19 mm. long. The first segment is twice as broad as long, 

 the second is somewhat longer, the third is rather longer than broad, and the fourth 

 and following are all approximately twice as long as broad. The ends of the segments 

 in the proximal half of the cirri are slightly enlarged, this feature gradually dying 



