no. 2073. HOLOTHURIANS FROM NORTHWEST PACIFIC— OHSHIMA. 239 



have a few more papillae than the outer (lateral), the former consisting 

 of 57-65 papillae, and the latter of only 52-60 in each. Besides the 

 deposits hitherto known, slender spinose rods occur in walls of genital 

 tubes, and small wheellike plates are abundantly found in longitu- 

 dinal muscles. 



It is scarcely to be doubted that Augustin had before him a speci- 

 men of this species. His figure of the wheel was probably drawn from 

 an incompletely developed one, in which the felly had not attained its 

 full thickness. 



Habitat — Numerous stations in Sagami Sea (Mitsukuri, 1912); 

 entrance of Tokyo Bay (Augustin, 1908); off Kii, Honshu. 



30. ILYOD^MON MIURENSE, new species. 

 Plate 8, figs. 9a-c. 



Station 5094. Five specimens. 

 Body very much like that of /. ijimai in external features, the 

 largest specimen is 75 mm. long, 22 mm. broad; length therefore 

 2.5-3 times the breadth. Mouth ventral, surrounded with 15 

 almost uniform-sized tentacles; anus terminal. Color gray, dorsal 

 papillae violet. Lateral pedicels in a single series, 20 in each, largest 

 ones 8 mm. long and 4 mm. across at base, diminishing in size back- 

 ward. Papillae form two rows along each dorsal ambulacrum, as 

 long as the lateral pedicels but only half as thick. The inner (median) 

 series consists of 33-36 papillae, while the outer (lateral) one always 

 contains fewer papillae, viz, 20-26. Deposits of general perisome in 3 

 kinds — large wheels, small wheellike plates, and complicated rosettes. 

 Large wheels (pi. 8, fig. 9a) are most numerous in ventrum, pedicels, 

 and tentacles, less numerous in dorsum. Spokes most commonly 9, 

 but may rarely vary from 7 to 12. Central holes are 6 in most cases, 

 but may vary from 4 to 8. Of these 6, three are alternately larger 

 and small, and over the larger ones there is a triradiate body which 

 grows out from the "Mittelpfeiler" as in I. maculatus The* el. 1 In 

 perisome diameter of these wheels varies between 160 and 260/z, with 

 a mean of 220/i, while in pedicels and papillae they are often as small as 

 60-80/£. Small wheellike plates (fig. 95) are as usual oval in outline, 

 with 4 central and 12 peripheral holes. They are abundantly found 

 in pedicels, papillae, tips of tentacles, peristomial region, and radial 

 muscles. Mean diameter SO/jl, range 24-45/£. Complicated rosettes 

 (fig. 9c) are found mingled with the small wheellike plates, and are 

 nearly the same size as the latter. Tentacles and pedicels have bent 

 spinous rods, often branched; papillae destitute of them. Delicate, 

 almost smooth, often branched, rods are found in peristomial region. 



i Th&l, 1882, pi. 36, fig. 15. 



