PART 5 A MONOGRAPH OF THE EXISTING CRINOIDS 759 



Thaumalometra parva A. II. Clark, Proc. Biol. Soc. Washington, vol. 21, 1908, p. 128 (listed; nomen 

 nudum); Proc. U.S. Nat. Mus., vol. 34, 1908, p. 231 (description; Albatross sta. 3697), p. 318 

 (Japan); Crinoids of the Indi.an Ocean, 1912, p. 217 (synonj'my; locality); Journ. Washington 

 Acad. Sci., vol. 5, 1915, No. 6, p. 215 (southern Japanese species; range and its significance); 

 Unstalked crinoids of the Siboga-Exped., 1918, p. 256 (in key; range), p. 257 (references). 



Thaumalomelra ctjpris A. H. Clark, Smith.sonian Misc. Coll., vol. 61, No. 15, 1913, p. 65 {Challenger 

 sta. 236; new name for Antedon alternala P. II. Carpenter, 1888, in part; Challenger Report, 

 pi. 32, figs. 5, 7-9); Journ. Washington Acad. Sci., vol. 5, No. 6, 1915, p. 215 (southern Japan, 

 range and its significance); Unstalked crinoids of the iSt'fcof/a-Expod., 1918, p. 255 (in key; range), 

 p. 256 (references). — Gisl^n, Nova Acta Reg. Soc. Sci. Upsaliensis, ser. 4, vol. 5, No. 6, 1922, 

 p. 147 (comparison with T. comaster); Ark. Zool., vol. 19, No. 32, 1928, p. 11 (notes). 



Thaumalomelra comaster Gisl£n (not of A. H. Clark), Nova Acta Reg. Soc. Sci. Upsaliensis, ser. 4, 

 vol. 5, No. 6, 1922, p. 5 (localities), p. 144 (description), pp. 180, 181 (listed); figs. 153-156, p. 

 146 (cirrus; pinnules); Zool. Bidrag Uppsala, vol. 9, 1924, p. 275 (shape of mouth), p. 283 

 (ambulacral groove); Vid. Medd. Nat. Foren. K0benhavn, vol. 83, 1927, p. 52. 



Diagnostic features. — The cirri arc XXX-XL, 9-15, the longest segments three 

 or four times us long as their median width when the arms are about 30 mm. long and 

 even longer, relatively, in smaller specimens; the antepenultimate segment is less than 

 twice as long as broad; Pi has 15 or more segments, 5 to 7 mm. long; P2 is shorter but 

 stouter and bears a gonad. The cirri are about 9 mm. long when the arms are 30 mm. 

 but may be relatively shorter. 



Description. — The centrodorsal is rather small, hemispherical or low conical, with 

 the cirrus sockets closely set in two or thi'ce crowded rows, leaving only a small portion 

 of the dorsal pole bare. 



The cirri are about XXX, 10-12, 9 mm. long. The first segment is about as long as 

 broad, the second is about half again as long as broad, the third and fourth are between 

 three and four times as long as broad, and the following gradually decrease in length so 

 that the oblong antepenultimate is about twice as long as broad, and the penultimate 

 is about half again as long as broad. The opposing spine is very small, in height less 

 than a third the width of the penultimate segment, terminally situated and directed 

 obliquely forward. The terminal claw is about as long as the penultimate segment, 

 rather stout and moderately curved. The second to fifth segments are constricted 

 centrally with expanded ends. Beyond the fourth the segments gradually become 

 broader dorsoventrally and laterally compressed. 



The distal edges of the radials are even with the rim of the centrodorsal. The IBri 

 are short, oblong, about four times as broad as long, somewhat narrower distally than 

 proximally, quite rounded dorsally and well separated laterally. The IBrj (axillaries) 

 arc rhombic, somewhat broader than long, with concave distal borders and a rather 

 sharp distal angle, and with a rounded posterior projection rising to a slight tubercle. 



The 10 arms are apparentlj- about 30 mm. long. The first brachials are wedge- 

 shaped with the exterior borders longer than the interior, and entirelj^ free interiorly'. 

 The second brachials are much larger and u-regularly quadrate. The fu-st syzygial pair 

 (composed of brachials 3+4) is somewhat longer than broad, and sliglilly longer 

 interiorly than exteriorly. Tlie fifth to eighth brachials are oblong, about half again 

 as broad as long, and the following become wedge-shaped and about as long as broad. 

 Only the pro.ximal third of the arms remains. 



Syzygies occur between brachials 3+4, 9+10, and 14 + 15. 



P, is very slender, 6 mm. long, with 15 segments, of which the first is very short, 

 the second and third are about as long as broad with their corners cut away, the fourth 



