NO. 1555. HA WA IIA N If OLOTHUHIANS— FISHER. 7 1 1 



pedicel."^ the central oiie.s have coimnonly only a few holes and numer- 

 ous peripheral diveroin^ simple or branched processes. 1 can tind no 

 moditied wheel plates similar to TheeVs fig. 12. Around the edge of 

 the disk of pedicels are a very few branched three or four armed rods, 

 probably growth stages of the plates. In the oral disk are numerous 

 rods similar to those herewith figured, about0.12 to 0.165 mm. in length 

 (fig. 2/t). Besides these are many small wheel-like plates, sometimes 

 irregular or imperfect (fig. 2e). In the end of the tentacles are many 

 long, curved, irregular spiny rods (2/) which frequently have the 

 ends forked. The}' vary much in size, but most of them are large, 

 commonl}' attaining a length of 0.8 or 0.95 mm. Theel figures rods 

 from tentacles, l)ut does not give dimensions. Presumabl}' his fig. 10 

 is drawn to scale, which would make the rods comparatively small. 

 The ditl'erence in these rods is the most striking that is discoverable 

 between the deposits of the two species. 



Both J\ iiwseleyl and Ludwig's variet}^ henrici. are of a very decided 

 violet or rose violet tint, but pallida is practically colorless, except 

 for a faint yellowish shade to the translucent body wall and the disks 

 of the tube feet, which are abruptly Indian red. (The color was 

 observed in the fresh animal by the writer.) This, combined with the 

 feeble development of the midventral series of pedicels, the perfectly 

 definite calcareous ring which is herewith figured, and some minor 

 diflerences in the calcareous deposits, especially in the presence of 

 long rods in the crown of the tentacles, seem to constitute specific 

 differences. Pallida is undoubtedly nearly related to moseleyl^ and 

 only future explorations in other localities will decide whether the 

 above ditlerences are constant. P. midtlradlata Sluiter has wheels 

 with fifteen to eighteen spokes. P. moseleyl was taken by the Cital- 

 lenger ofl' Sydney in 950 fathoms and off New Zealand in TOO fathoms, 

 both from gray ooze. 



Family CUCUMAKIID.F: Ludwig. 



CucuvKiriicht' Ludwig, Mem. Muh. Coiiip. ZooL, Harvard College, XYII, no. 3, 

 1894, pp. 7, 122. 



Subtkinil>- CXTCXTMA.FtII]Sr^*: R. Perviei-. 



Cucumariitnv Perkiek, Holothuries, Exped. du Travailleur et du Talisman, 1893, 



p. 492. 

 ^ Genus THYONIDIUM Dliben and Koren. 



Thyonklium Duben and Koren, Kongl. Vet. Akad. Handlingar, 1844, p. 214. 

 Type, Th. coynmtme Duben and Koren = Th. drummondi (Thompson). 



According to Theel: 



Tentacles 20, exceptionally fewer or more, five pairs of larger alternating with five 

 pairs of smaller. Ambulacral appendages in the shape of pedicels sometimes densely 

 crowded, sometimes more thinly scattered; often an arrangement of them in rows 

 distinguishable along the ambulacra. 



