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THE VOYAGE OF H.M.S. CHALLENGEE. 
Orcula cucumiformis, Semper, 1868. 
Larger pedicels in a double row along the ambulacra, and a few smaller scattered on 
the interambulacra. Calcareous ring of ten simple pieces, the radial with two 
posterior prolongations composed of several separate pieces or joints. Deposits — 
large scattered plates. 
Habitat. — Cape York (Semper), Port Molle (Bell). 
The following two species of Orcula are unsatisfactorily known : — 
Orcula punctata, Selenka, 1867 and 1868. 
Habitat. — Charleston (Selenka). 
A very dubious form. Judging from the first description of Selenka, one must feel 
inclined to refer it to the northern form Orcula barthii, but lately in his 
“ Nachtrag ” Selenka declares Orcula punctata of Agassiz to he identical with 
Thyonidium productum, Ayres. Selenka, however, does not explain whether 
his Orcula yunctata, described in 1867, represents the type of Agassiz mentioned 
by Selenka in 1868. Besides, it remains unexplained how Thyonidium productum, 
with twenty tentacles, and Orcula punctata, with fifteen tentacles, can be 
synonymous. 
Orcula lapidifera [Holothuria), Lesueur, 1824 ; Semper, 1868. Phyllophorus (F) 
lepadifera, Verrill, 1867-1871. 
Tentacles sixteen. Incomplete description. Possibly belonging to another genus. 
Habitat. — St. Bartholomew (Lesueur). 
Genus 13. Phyllophorus, Grube, 1840. 
Tentacles forming two crowns, twelve to sixteen in the exterior and five to six in the 
interior. Ambulacral appendages almost without exception in the shape of 
pedicels, irregularly distributed all over the body. 
I. Pedicels cylindrical, all of the same shape. 
1. Deposits in the shape of rods. 
Phyllophorus perspicillum (C/roc?emas), Selenka, 1867; Semper, 1868. Orcula perspi- 
cillum, Semper, 1868. 
Fifteen larger tentacles in the exterior crown, and five smaller (?) in the interior 
Deposits — spectacle-like rods with a hole at each end, sometimes also with a 
