A MONOGRAPH OF THE EXISTING CRINOID8 185 



a 1 . PI (and P D when present) shorter and more slender than P,. 



ft 1 . Cirri gradually tapering to a sharp point distally, the distal cirrus segments proportionately as 

 long as, or longer than, the proximal, twice as long as broad or even longer, and entirely 

 without dorsal processes; no opposing spine; terminal claw long and nearly straight; outer 

 portion of cirri very slightly, sometimes not at all, recurved. 



c 1 . Cirri very long and stout, one-third to almost half as long as the arms, with 40-60 (usually 

 45-50) segments; proximal portion of the cirri light in color, each segment with a ventral 

 purple saddle, the distal portion brown; division series usually broad, well rounded dorsally, 

 not in lateral contact; large and robust with 20-36 arms 90-130 mm. long (Philippines 

 and Hongkong southward to Amboina and westward to Andaman Islands and Gulf of 



Martaban; 0-33 meters) Craspedometra (p. 214) 



c 1 . Cirri small and very slender, less than one-third the arm length, with 25-30 segments, and 

 entirely white; slender species with 10 or 11 arms 70-90 mm. long (Arafura Sea to western 



end of New Guinea; 90-95 meters) Homalometra (p. 337) 



b*. Distal cirrus segments always with dorsal tubercles or spines, and the terminal claw always 

 strongly curved; distal cirrus segments usually shorter than the proximal, or both distal and 

 proximal cirrus segments broader than long. 



c 1 . More than 10 arms; enlarged lower pinnules much elongated, plain, or with the lower seg- 

 ments carinate, or the outer segments bearing flange-like processes or having very spinous 

 distal ends; in some species 10-armed individuals occur; these are easily distinguished by 

 the strongly carinate or otherwise modified proximal pinnules (southern Japan southward 

 to Port Curtis, Queensland, and Baudin Island, northwestern Australia, and westward to 

 Madagascar and east coast of Africa from Red Sea to Zanzibar and Bagamoyo; 0-111 



meters) Heterometra (p. 225) 



<?. Arms 10; enlarged lower pinnules but slightly differentiated from those following, not much 

 enlarged and but little elongated; occasional individuals may have more than 10 arms; 

 in these the IIBr series are 2 instead of 4(3 + 4) (southern Japan southward to the Philip- 

 pines, Fiji, and Tonga, Port Molle, Queensland, and to between Fremantle and Geraldton, 



Western Australia, and westward to Maldive Archipelago; 0-109 [?183] meters) 



Amphimetra (p. 340) 

 Genus HIMEROMETBA A. H. Clark 



Aclinometra (part) P. H. CARPENTER, Notes Leyden Mus., vol. 3, 1881, p. 201. 



Antedon (part) HARTLAUB, Nachr. Ges. Gottiugen, May 1890, p. 182, and following authors. 



Himerometra A. H. CLARK, Smithsonian Misc. Coll., vol. 50, 1907, p. 350 (variation in the component 

 species), p. 355 (diagnosis; genotype Anledon crassipinna Hartlaub, 1890); Bull. Mus. Comp. 

 Zool., vol. 51, 1908, p. 247 (characters; genotype Anledon crassipinna Hartlaub, 1890); Proc. 

 Biol. Soc. Washington, vol. 21, 1908, p. 135 (referred to Himerometridae) ; Proc. U. S. Nat. 

 Mus., vol. 34, 1908, p. 211 (referred to Himerometridae), p. 212 (occurs in Japan [error]), 

 pp. 308, 317; vol. 35, 1908, fig. 20, p. 120 (arm structure); Amer. Nat., vol. 42, 1908, p. 722 

 (ecology); Proc. Biol. Soc. Washington, vol. 22, 1909, p. 1 (revision), p. 7 (included species, as 

 restricted); Amer. Nat., vol. 43, 1909, p. 256 (absence from Red Sea); Zool. Anz., vol. 34, 1909, 

 p. 367 (arm division similar to that of Zygometra elegans) ; Proc. Biol. Soc. Washington, vol. 22, 

 1909, p. 175 (referred to Himerometrinae) ; Vid. Medd. Nat. Foren. K0benhavn, 1909, p. 152 

 (brachials compared with those of Zygomelra flucluans [comata]), p. 160 (brachials compared 

 with those of Craspedomelra acuticirra) ; Die Fauna Sudwest-Australiens, vol. 3, Lief. 13, 1911, 

 p. 455 (a specimen of Comanthina belli recorded with the arm division characteristic of this 

 genus); Mem. Australian Mus., vol. 4, 1911, p. 725 (absent from Australia); Crinoids of the 

 Indian Ocean, 1912, p. 9 (absent from Australia), p. 10 (absent from Japan; reason), p. 11 

 (represented in Ceylon region; this the western limit of the large and highly multibrachiate 

 species), p. 12 (occurs in Persian Gulf but not in Red Sea), p. 21 (range in detail), p. 56 (in key), 

 p. 114 (original reference; genotype). HARTLAUB, Mem. Mus. Comp. Zool., vol. 27, 1912, pp. 

 370, 371 (discussion). A. H. CLARK, Die Fauna Sudwest-Australiens, vol. 4, Lief. 6, 1913, p. 

 311 (comparison with the large species of Zygometridae) ; Proc. U. S. Nat. Mus., vol. 46, 1913, 

 pp. 279-289 (detailed account, with revision of the included species) ; Unstalked crinoids of the 

 208244 40 13 



