no. 2073. HOLOTHURIANS FROM NORTHWEST PACIFIC— OHSHIMA. 253 



4, the number of holes varies 30-50, with a mean of 40. Mean diam- 

 eter of disks 420 /*, with a range of 27 '0-550 /*. In caudal appendage 

 the disks are regularly spindle-shaped, with very minute holes and a 

 low spire. 



M. dissimilis Clark seems to present a close resemblance to the 

 present species. But the tables and anchors are four-rayed in our 

 species and three-rayed in dissimilis. 



Habitat. — Suruga Bay (Mitsukuri, 1912). 



Type— Cut. 34161, U.S.N.M. 



48. MOLPADIA CLARKI, new species. 

 Plate 9, figs. 14a-c. 



Station 4983. Two specimens. 



The more or less distorted body measures 43 mm. long including 

 the caudal appendage which is 8-12 mm. Color gray all over, with a 

 slight tinge of purple. Integument soft but rough from the presence 

 of anchors. Tentacles 15, each with a pair of small digits. Deposits 

 much resembling those of M. roretzii but larger and more irregular. 

 Tables (pi. 9, figs. 14a, b) have disks of irregular contour, often 

 excentric with regard to the primary cross. Mean diameter 200/*, 

 ranging between 110 and 340/*, holes 7 or 8 in number, varying from 

 2 to 24. Spire about 160/1 high, composed of 3 pillars, and armed 

 with 9 or more teeth at the top and often some more on the sides. In 

 the anterior region these tables are small and simple. Tables of the 

 caudal appendage (fig. 14c) are elongated, measuring 240-450/* in 

 length, with a spire about 100/* high. Racket-shaped bodies are 

 about 715//. in average length, ranging between 460 and 840/*, similar 

 in shape to those of M. roretzii but plumper and with smaller holes. A 

 rosette is composed of 5 of these bodies in most cases, but the number 

 may vary from 3 to 10. Anchors measure 480-520/* in length, with a 

 base 80-105/* in diameter, and bearing on each arm 4, or sometimes 3 

 or 5, prominent teeth. Anal teeth forked at base, measuring 600/* 

 by 300/*. Phosphatic corpuscles about 30-120/* in diameter. Radial 

 segments of calcareous ring have a rather long posterior prolongation 

 bifurcated at the end. Polian vesicle and stone canal single. Res- 

 piratory trees 2, the right one being twice as long as the other. 



The present species differs from M. productamensis Clark in some 

 minor points. In this Japanese species the bifurcation of posterior 

 prolongations of calcareous ring is not very deep, spire of tables has 

 fewer crossbeams, and elongated tables in caudal appendage are larger 

 and more robust. It is my great pleasure to name this species for 

 Dr. Hubert Lyman Clark, of the Museum of Comparative Zoology, 

 Harvard College. 



Habitat. — Off the coast of Shiribeshi, Hokkaido. 



Type.— Cat. No. 34162, U.S.N.M. 



