no. 2073. HOLOTHURIANS FROM NORTHWEST PACIFIC— OHBHIMA. 279 



83. PHYLLOPHORUS MINUTUS, new species. 

 Plate 11, figs. 31a, b. 



Station 4900. Two specimens. 

 Body indistinctly pentangular, with bluntly ending extremities, 

 13.5 mm. in length and 5 mm. in diameter, Integument thin and 

 soft', smooth to the touch, white all over. Tentacles 20, of 2 different 

 sizes; 10 interradial larger than the 10 radial, which form an inner 

 circle. Pedicels retractile, forming a zigzag or double row along each 

 ambulacrum. Very minute pedicels invisible to the naked eye scat- 

 tered in the three dorsal interambulacra. Deposits of general peri- 

 some are table-like buttons, quite regular in shape (pi. 11, figs. 31a, h); 

 disk quadrangular or rhombic, with large holes numbering from 4 to 

 10, usually 8; mean diameter of disks about 83//, range 60-120/*. 

 From the central bar, which separates the 2 pairs of largest holes, arise 

 a pair of pillars which unite once and give off 4-8 short teeth at the 

 top. Height of spire, 20-27/*. In the introvert the tables are slightly 

 smaller, 45-1 00//, often irregular and rod-like in shape. In pedicels 

 are found much robust and elongated tables with 2 pairs of holes at 

 the middle and a few at each end. The two prolongations of the disk 

 often do not he in a straight line as in Ph. dlexandri (Fisher). End 

 plates of pedicels larger in the ambulacra, measuring 220-280/* in 

 diameter, in the interambulacra only 100-200/*; single small end 

 plates often representing rudimentary pedicels. Supporting rods of 

 tentacles smooth, with expanded or branched ends perforated by 

 minute holes. Anus with 5 teeth and 10 papillas. Calcareous ring 

 similar to that of Ph. intermedins Koshler and Vaney, only differing in 

 that the anterior margin is not oblique and in that the segments are 

 united together by one-half of their length. Extractors inserted to 

 body wall slightly behind the middle of body, the midventral one 

 being most anterior. Polian vesicle and stone-canal single. Genital 

 tubes apparently immature, unbranched, few in number. Respira- 

 tory trees 2. 



This species stands very close to Ph. intermedins in many respects, 

 but differs from it in the shape of the calcareous ring and deposits. 

 Ph. dlexandri from Hawaii is also very nearly allied to the present 

 species, but differs by the presence of numerous pedicels in the dorsal 

 interambulacra, besides having calcareous ring and tables of different 

 shapes. 



Habitat. — Off Goto Islands, west of Kyushu. 



Type.— Cat. No. 34182, U.S.N.M. 



