144 HOLOTHURIIDAE. 



Station 4656. Eastern Tropical Pacific, 6° 54' 36" 8., 83° 34' 18" W., 2,222 fms. Bott. temp. 35.2°. 

 Fne. gn. m., mang. nod. 



One specimen. 



Mesothuria multipora, ' sp. nov. 

 Plate 4, fig. 11-13. 



Length, 140 mm.; diameter, about 50 mm. Color, gray. Internal 

 anatomical details not definable as the specimen has eviscerated. Pedicels 

 scattered all over body, but most sparsely dorsally; dorsal pedicels about 

 1 mm. long by .25 mm. in diameter; the pedicels are much more numerous and 

 twice as large along the sides. Skin in close, horizontal, nearly black folds 

 along each side, forming a fairly distinct border between dorsal and ventral 

 surfaces. 



Calcareous particles present in the form of tables (Plate 4, fig. 11) alone. 

 These are all of the same type and show diversity chiefly in the number of per- 

 forations in the disk; spire with one cross-beam, about 75m high and 50m 

 across the top (Plate 4, fig. 13) which bears about sixteen teeth; disk (Plate 4, 

 fig. 12) squarish, 200 m across, with a somewhat square central hole and thirty 

 to fifty more or less circular perforations of small size. 



Station 74. Tahiti: 4.8 miles N., 82° W. from Point Venus, 772 (?) fms. Bottom temp.? Fne. vol.s. (?). 



One specimen. 



This specimen was labeled by Professor Mitsukuri "Mesothuria intesti- 

 nalis Asc. Rathke (Hoi. Verrillii Theel)." I have compared it with both 

 intestinalis from Norway and cotypes of verrilli from the West Indies, and the 

 difference in the tables is striking and apparently constant. I am satisfied 

 that verrilli is a perfectly valid species and that the present Tahitian form is 

 entirely distinct from either the European or the West Indian species. 



Synallactes aenigma. 

 Plate 3, fig. 4. 

 Ludwig, 1893. Bull. M. C. Z., 24, p. 106 (nomen nudum). 1894, Mem. M. C. Z., 17, p. 26. 



This seems to be one of the characteristic species of the Eastern Tropical 

 Pacific and the present series throws no little light on its structure and varia- 

 bility. Instead of merely eviscerating, this species seems to have also the unusual 

 habit of actually throwing off the skin. Either as a result of rough treatment 

 in the trawl or because of the decreased pressure at the surface, or perhaps for 

 both reasons, the skin, which is quite thick and tough splits down the middorsal 



1 multiporus = having many pores, in reference to the disk of the calcareous tables. 



