A MONOGRAPH OF THE EXISTING CRINOIDS 7 



In a paper on crinoids collected by the Albatross in the Philippines published on 

 February 15, 1911, the new genus Epimetra was described and assigned to the family 

 Pontiometridae, and in the family Colobometridae new species of Cenometra, Colobo- 

 metra, Cyllometra, and Oligometra were recorded. In a revision of the family Maria- 

 metridae published by the author on June 30, 1913, the family Pontiometridae was 

 suppressed, the genus Pontiometra being referred to the Mariametridae, and the 

 genus Epimetra to the Colobometridae. In a paper on the crinoids of the Buitenzorg 

 Museum published in December, 1933, the genus Pontiometra was definitely assigned 

 to the family Colobometridae. 



KEY TO THE GENERA OF THE FAMILY^COLOBOMETRIDAE 



a 1 . More than 50 arms; cirri with more than 46 segments. 



&'. PI on the outer arms greatly elongated, rather slender and evenly tapering, 22-40 mm. in 

 length with 20-56 segments, several times as long as the short P 2 , which is 3.5-7 mm. long 

 with 8 or 9 segments (Part 2, fig. 277, p. 213) and resembles the pinnules following; all the 

 pinnules present; division series all 2 (or occasional ones very exceptionally 4[3 + 4]); cirri 

 very long and stout with 41-80 (rarely less than 60) segments; 53-120 (seldom less than 60) 

 arms; large and stout, with the arms 105-180 mm. long (from the Philippine and Pelew 

 Islands southward to New Caledonia and the Kei Islands, and westward to the Andaman 



Islands and the Mergui Archipelago; 0-73 meters) Pontiometra (p. 9) 



b 1 . PI, P2, and P, similar and of the same length, very stiff and rigid, 23-24 mm. long with 17 or 18 

 segments; P 4 similar, but shorter; P. always absent, and PI, P 3 , P., and P b usually absent 

 on the inner arms arising from each IIBr series; IIBr series 4(3 + 4); IIIBr series 2; follow- 

 ing division series 4(3 + 4); cirri long and moderately stout with 47-49 segments; 80 arms 



120 mm. long (Ternate; 2-4 meters) Basilometra (p. 21) 



a'. Less than 40 arms; not more than 46 cirrus segments. 



&'. P 2 very stout, abruptly larger and stiff er than PI or Pj, recurved and hornlike, the 11-23 

 (usually 15-20) segments with produced and spinous distal ends (Part 2, figs. 274, 278, 

 p. 213); cirri stout, strongly curved, with 28-45 segments all of which are much broader 

 than long and bear dorsally paired spines or tubercles; 12-39 arms; size medium or large, 

 the arms 85-140 mm. long (from the Bonin and Philippine Islands southward to north- 

 western Australia and westward to Ceylon, the Seychelles, and Mauritius; 0-55 [?66] 



meters) Cenometra (p. 26) 



b-. P 2 not hornlike and abruptly stouter and stiffer than P, or Pj. 



c l . Third and fourth or third-fifth segments of the genital pinnules broadened to protect the 



gonads; 10 arms. 

 d l . Cirrus segments, at least in the outer half of the cirri, with dorsal processes, a transverse 



ridge, row of spines, or a single spine flanked by a smaller one on each side. 

 e 1 . All the cirrus segments except the penultimate bear a dorsal transverse ridge or row of 



spines. 



/'. Cirrus segments with a prominent median transverse ridge appearing in lateral view 

 as a small median spine; PI longer and stouter than P 2 , which is longer than Pjj 

 all the pinnules present (from Wollongong, New South Wales, to Bass Strait, 102 



[?100]-128 meters) Austrometra (p. 52) 



f 1 . Cirrus segments with the dorsal distal edge thickened and finely spinous; P 2 longer 

 than P! or P>; P. and usually also other proximal pinnules absent (off the Cape of 



Good Hope; 293-325 meters) Embryometra (p. 251) 



e 2 . The segments in the distal half of the cirri bear dorsally a prominent median spine which 

 at first is flanked on each side by a much smaller spine, but later stands alone ; 10 arms 

 15-60 mm. long (from the Florida Straits and the Bahamas to Barbados and Colon; 



5.5-64 meters) Analcidometra (p. 77) 



d 2 . Cirrus segments smooth dorsally, without dorsal processes; PI stout, stiff, and styliform 

 with 6-9 segments; P 2 longer and curved; all the pinnules present (southeastern Africa 

 from East London to Durban; 238 [7146J-567 meters) Gislenometra (p. 57) 



