362 BULLETIN 82, UNITED STATES NATIONAL MUSEUM 



1, pt. 3, 1914, p. 124 (comparison with discoidea and jacquinoti); Internal;. Revue gesamt. 

 Hydrobiol. und Hydrogr., 1915, pp. 223 S. (detailed account of the distribution in Australia) ; 

 Unstalked crinoids of the Siboga-E\ped., 1918, p. 89 (references; identity doubtful; notes). 

 GISLEN, Kungl. Svenska Vet.-Akad. Handl., vol. 59, No. 4, 1919, p. 3 (listed), p. 5 (stations 6, 

 8, 9, 11), p. 26 (description of the specimens), pi. 1, fig. 6. 



Amphimetra lessellata A. H. CLAKK, Proc. Biol. Soc. Washington, vol. 22, 1909, p. 7 (listed); Un- 

 stalked crinoids of the iSiboja-Exped., 1918, p. 90 (references; notes; identity doubtful). 



Amphimetra discoidea A. H. CLARK, Die Fauna Sudwest-Australiens, vol. 3, Lief. 13, 1911, p. 444 

 (Perth), p. 459 (?vicinity of Perth; notes); Proc. U. S. Nat. Mus., vol. 43, 1912, p. 393 (Western 

 Australia; refers to the specimen from ?vicinity of Perth). ALEXANDER, Rec. Western Austral- 

 ian Mus., vol. 1, pt. 3, 1914, p. 108 (between Fremantle and Geraldton). A. H. CLARK, Rec. 

 Western Australian Mus., vol. 1, pt. 3, 1914, p. 114 (collected by the Endeavour in 

 Western Australia), p. 115 (Australian tropical species; occurrence in the vicinity of Perth 

 established), p. 123 (between Fremautle and Geraldton, 60-100 fathoms; notes; compari- 

 sons); Internat. Revue gesamt. Hydrobiol. und Hydrogr., 1915, p. 223 ff. (part; detailed account 

 of the distribution in Australia). HARTMEYER, Mitt. zool. Mus. Berlin, vol. 8, Heft 2, 1916, 

 p. 235 (Western Australia; in the Hamburg Museum; refers to the specimen from ?vicinity of 

 Perth). 



Amphimetra jacquinoti A. H. CLARK, Rec. Western Australian Mus., vol. 1, pt. 3, 1914, p. 124 (com- 

 parison with discoidea and milberti [ = spectabilis]) ; Unstalked crinoids of the <Si6o0a-Exped., 

 1918, p. 83 (in key; range), p. 85 (references; detailed description; Stas. 33, 164; additional locali- 

 ties), pp. 271, 273 (listed), pi. 18, fig. 36. H. L. CLARK, The echinoderm fauna of Torres 

 Strait, 1921, pp. 192 and following (range). A. H. CLARK, Temminckia, vol. 1, 1936, p. 302 

 (Amboina; 0-2 meters; notes). GISLEN, Kungl. Fysiogr. Sallsk. Lund Forh., vol. 7, No. 1, 

 1936, p. 4 (French Indochina), pp. 5, 6 (range), p. 11 (locality; notes). H. L. CLARK, Mem. 

 Mus. Comp. Zool., vol. 55, 1938, p. 35 (Broome; notes). 



Helerometra jaquinoti GISLEN, Zool. Bidrag Uppsala, vol. 9, 1924, p. 39, footnote (disk reaches to the 

 sixth brachial) ; p. 41 (details of arms), p. 42 (braehial angles), p. 53 (axillary angle). 



Diagnostic features.- The cirri are large and stout, more or less straight proximally, 

 curved distally, with the longest proximal segments varying from nearly twice as 

 broad as long to nearly as long as broad; the cirri are 30-50 mm. long, with 35-47 

 segments, the earlier sometimes with a broad transverse ridge or paired spines; the 

 arms are 130-300 mm. long, usually 10, occasionally 11 or 12. 



Description. The centrodorsal is thick discoidal, more rarely more or less hemi- 

 spherical, 6-8 mm. in diameter at the base; the bare dorsal pole is usually broad, 

 about 3 mm. in diameter, and is usually more or less convex, less commonly flat, and 

 sometimes with a small median pit. The outer margin of the dorsal pole is more or 

 less swollen at the bases of the adjacent cirri. The cirrus sockets are arranged in 

 usually two closely crowded alternating rows. 



The cirri are XVII-XLIII (usually XX-XXX), 26-47 (usually 35-40), in fully 

 grown individuals 30-50 (usually 35-40) mm. long. The cirri are large and stout, 

 becoming laterally compressed distally. They are commonly stout basally, tapering 

 very appreciably distally; but they may be, in lateral view, of uniform width through- 

 out, or broader in the compressed distal portion than proximally, the last two types 

 being sometimes found in the same individual. The first segment is very short, up 

 to twice as broad as long or even broader, those following gradually increasing in 

 length to the sixth to ninth, which, with a few of those following, are from twice as 

 broad as long to nearly as long as broad, most commonly about half again as broad as 

 long. The segments following are shorter. The longer earlier segments have slightly 



