A MONOGRAPH OF THE EXISTING CRINOIDS 421 



though they are somewhat more compressed and deeper proximally and sharply 

 rounded instead of carinate distaily. 



The pinnules are essentially as in P. trichopoda, but are slightly stouter. 



Locality. Albatross station 5179; in the vicinity of Romblon; Romblon Light 

 bearing S.56 E., 4.5 miles distant (lat. 12 38'15" N., long. 12212'30" E.), 68 meters; 

 bottom temperature 24.28 C.; hard sand; March 25, 1908 (A. H. Clark, 1909, 1912, 

 1918] (1, U. S. N. M., 25517). 



History. This species is still known only from the single specimen collected by 

 the Albatross in 1908. 



PTEROMETKA TEICHOPODA (A. II. Clark) 



[See vol. 1, pt. 1, fig. 46 (arm tip), p. 81; pt. 2, fig. 203 (lateral view), p. 137; fig. 208 (lateral view), 

 p. 146; figs. 513, 514 (pinnule tip), p. 276; fig. 659 (articular face of a pinnular), p. 329.] 



Ptilqmetra trichopoda A. H. CLARK, Smithsonian Misc. Coll., vol. 52, part 2, 1908, p. 224 (description; 

 Albatross station 5153; also station 5179); Proc. Biol. Soc. Washington, vol. 22, 1909, p. 40 

 (comparison with P. dorcadis); Proc. U. S. Nat. Mus., vol. 37, 1909, p. 34 (compared with 

 P. splendida). 



Pterometra trichopoda A. H. CLARK, Proc. U. S. Nat. Mus., vol. 39, 1911, p. 545 (Albatross stations 

 5356, 5413, 5414, 5593) ; Zool. Anz., vol. 39, No. 11/12, 1912, p. 424 (compared with P. venusla) ; 

 Crinoids of the Indian Ocean, 1912, p. 190 (synonymy; range), fig. 32, p. 191; Die Crinoiden 

 der Antarktis, 1915, p. 124 (shows characteristic features of Anthometra adriani); Unstalked 

 crinoids of the Siboga-Exped., 1918, p. 143 (in key; range); Smithsonian Misc. Coll., vol. 72, 

 No. 7, 1921, pi. 1, fig. 14 (arm tip). GISLN, Nova Acta Reg. Soc. Sci. Upsaliensis, ser. 4, vol. 5, 

 No. 6, 1922, p. 5 (145-182 m.), p. 6 (Bonin Islands), p. 99 (Bock's stations 75, 48, 59; detailed 

 notes), pp. 182, 183 (listed), figs. 101, 102, p. 122; Zool. Bidrag Uppsala, vol. 9, 1924, p. 44, fig. 

 287, p. 209, figs. 293, 294, 296, 298, p. 217. SIEVERTS, Neues Jahrb. Min., Geol. und Pal., vol. 

 69, Beilage-Band, Abt. B, 1932, pp. 151, 156. GISLN, Kungl. Fysiogr. Sallsk. Handl., new 

 ser., vol. 45, No. 11, 1934, pp. 20, 25; Kungl. Fysiogr. Sallsk. Lund Forh., vol. 7, No. 1, 1936, 

 p. 19 (relation to P. venvsta). 



Diagnostic features. -The earlier cirrus segments have the ventral portion of the 

 distal edge raised and overlapping the bases of the segments succeeding with the 

 midventral portion produced into a sharp spine; the proximal portion of the animal 

 in constricted, the profiles of the division series and arm bases diverging from the 

 centrodorsal at an angle of about 45; the cirri are XV-XXII, 60-108 (usually 70-90), 

 from 60 to 80 mm. long; the 20-30 arms are 60-75, rarely as much as 150 mm. long; 

 the color is violet or purple striped and blotched with white. 



Description. -The centrodorsal is columnar, the polar area a low truncated cone 

 bearing five rather long rounded tubercles which are radial in position. The cirrus 

 sockets are arranged in 10 columns, 2 columns in each radial area, with usually 2 

 cirrus sockets to a column. 



The cirri are XX, 80-85 (usually 84 or 85), 60 mm. long, very long and slender, 

 tapering gradually from a moderately stout base to a slender tip. The first segment 

 is short, the second is about twice as broad as long, and those following gradually 

 increase in length to the fifth, which is about as long as broad, and the eighth, which 

 is not quite half again as long as broad. The segments succeeding as far as the 

 eighteenth or twentieth are similar to the eighth, after which they gradually decrease 

 in length, the thirty-second to the thirty-fifth being about as long as broad and those 

 following gradually becoming broader than long, the terminal segments being very 

 short. The segments from the fourth to about the sixteenth, though smooth dorsally, 



