REPOET O^r THE HOLOTHURIOIDEA. 
133 
A. Anus with five calcareous teeth. 
I. Calcareous ring composed of ten simple pieces, devoid of posterior prolongations. 
Thyone suspecta, Ludwig, 1875, 
Deposits very rare, but present in two forms — oval plates with uneven margin and 
about four holes ; and ci;ps likewise pierced with four holes and with the rim 
uneven. Pedicels with numerous supporting rods. 
Hahitat . — Barbados (Ludwig). 
Ludwig supposes this species to be identical with Thyone h'aziliensis of Verrill, but if 
the statements of Yerrill be right, it seems more credible that Ludwig’s species 
is distinct, Thyone hraziliensis heing probably synonymous with Thyone hriareus. 
Ludwig mentions twenty tentacles, which evidently is a misprint. 
Thyone surinamensis, Semper, 1868, 
Deposits — closely crowded, knobbed buttons ; and scattered tables without disks. 
Anal teeth minute. 
Hahitat . — Surinam (Semper). 
Thyone spectabilis, Ludwdg, 1882. 
Deposits — slightly curv^ed rods with the ends perforated, branched, or spinose. 
Hahitat . — Strait of jMagellan (Ludwig). 
(Mus. Holm.) Numerous large specimens dredged during the “ Eugenie ” Expedition 
at Cape Virgins. This large Thyone is characteristic, agreeing in all respects 
with the description of Ludwig. Colour, yellowish-brown. Tentacles large, of 
equal size. Pedicels evidently more crowded on the ventral than dorsal surface, 
posteriorly more limited to the ambulacra. Calcareous ring rather solid, without 
any posterior prolongations. Polian vesicle and madreporic canal single. The 
smooth or slightly spinose rods are not very close together. 
II. Calcareous ring composed of ten simple pieces, the radial with a 
bifurcate prolongation posteriorly. 
1. No deposits in the hody-ivall itself. 
Thyone hriareus {Holothuria), Lesueur, 1824; Selenka, 1867. Anaperus hriareus, 
Pourtalfes, 1851. Sclerodactyla hriareus, Ayres, 1854 and 1873. (?) Thyone 
[Sclerodactyla) hraziliensis, Verrill, 1867-1871. 
Deposits of the pedicels — terminal plates and tables with rod-like disk. Calcareous 
ring of ten simple pieces, firmly grown together ; the radial with bifurcate 
prolongations posteriorly. 
