TROPICAL PACIFIC HOLOTIIIRIOIDKA. 143 



HOLOTHURIIDAE. 



Mesothuria megapoda,' sp. nov. 

 Plate 4, fig. 9, 10. 



Length about 40 mm. Color, pinkish white. Eviscerated and in bad 

 condition so even the generic position is not certain, but the calcareous tables 

 show such similarity to those of M. murrayi and M. multipes that there is little 

 doubt the specimen represents a species of Mesothuria. Body rather uniformly 

 covered with large pedicels, 2-3 mm. long and .50-.75 mm. in diameter; there 

 is no arrangement in series or bands, nor are any of the pedicels conspicuously 

 larger than the others. There are no supporting rods in the pedicels but there 

 are well-developed terminal plates. 



Calcareous particles consist of very numerous tables (Plate 4, fig. 9) with 

 spires 100-135 p. high; the three rods making up the spire are enlarged, curved 

 outwards and rough at the tip. The disks (Plate 4, fig. 10) are 150-200 n across 

 and are perforated with seven nearly equal holes, one at center with six around 

 it; while they are not all exactly alike, they exhibit little diversity. 



Station 4742. Eastern Tropical Pacific, 0° 3' 24" N., 117° 15' 48" W., 2,320 fms. Bott. temp. 34.3°. 

 Fne. It. gy. glob. oz. 



One specimen. 



.Although the specimen is in such poor condition its specific characters 

 are well marked. It is distinguished at once from M. multipes by the larger 

 pedicels, the presence of a well-developed terminal plate and the larger, lower 

 tables. In multipes, the disks of the tables are only 75-100 p. across, while 

 the spires are much more than that. From M. murrayi, megapoda may be 

 readily distinguished by the uniform and large size of the pedicels and by the 

 difference in the tables. In murrayi, the disks are only 70-120 n across but 

 have more numerous perforations. 



Mesothuria multipes. 



Mesites multipes Ludwig, 1893. Bull. M. C. Z., 24, p. 106. 

 Mesothuria multipes Ludwig, 1894. Mem. M. C. Z., 17, p. 31. 



The specimen at hand has eviscerated so nothing can be said of its internal 

 anatomy. Otherwise it agrees well with Ludwig's description except that the 

 tentacles are very dark colored, deep purplish. It is 60 mm. long. 



1 nt-y&iro&os = having large feet, in reference to the unusually large pedicels. 



