ECHINODERMATA, 15% 
feet or ambulacral tubes (CuviER), or the union of both these 
characters (BranpT) into many genera. The arrangement of 
Branpt is circumstantial, and here and there rather artificial than 
natural. Regard ought also to be had to the Habitus. If the 
position of the Tentacles be made the chief point in the arrange- 
ment, animals will be separated which in their habitus are nearly 
allied. These tentacles are either branched like a tree, fingered, or 
shield-like, (peltate), 7. e. they consist of a pedicle with an expansion 
which is disciform, often indented or arborescent. Their number is 
usually ten, or twice ten. Where eight tentacles seem to be present, 
sometimes on closer inspection two others, smaller and undeveloped, 
are found, (the sub-genera Anaperus and Colochirus of TRoscHELL'). 
In some no special internal respiratory organs are found (the genus 
Oncilabes of Branpt ; in most the arborescent respiratory organ 
exists which we described above in Holothuria tubulosa. 
Pentacta GOupF. (Cladodactyla, Dactylota, Oncinolabes, Aspido- 
chir Branpt). Feet equal, disposed in five, or, more rarely, in six 
rows longitudinal, parallel. Body cylindrical or quinquelateral, 
attenuated at both ends. ‘Tentacles mostly ten, sometimes twelve 
or fifteen. 
a) Tentacles peltate. 
Aspidochir Branpt. A genus unknown to me. Sp. Aspidochir 
Mertensii, in the island Sitcha (Tentacles 12). 
b) Tentacles ramose. 
Cladodactyla BRANDT (Tentacles ro). 
Sp. Pentacta Pentactes, Holoth. pentactes MuELL. Zool. dan. Tab. 31, fig. 8, 
Forbes Brit. Starf. p. 213 ; Pentacta frondosa, Holoth. frondosa L., Holoth. 
pentactes ABILDG. Zool. dan. Tab. 108, figs. 1, 2, Tab. 124. Fors. Br. Starf. 
p- 209 ; in the European seas. Pentacta doliolum, Actinia doliolum Pau. 
Spic. Zool. Tab. x1. figs. 1o—12. Cuv. R. Anim. éd. ill. Zooph. Pl. 20, 
fig. 4. These species are called, from their external resemblance, Sea- 
Cucumbers. 
c) Tentacles digitate or pinnate. 
Dactylota BRANDT. 
Sp. Pentacta pellucida, Holoth. pellucida, Zool. dan. Tab. 135, fig. 1. 
(Note.—Here also is to be referred the genus Ocnus Forsxs, Brit. Starf. 
p- 229.) 
1 Neue Holothuriengattungen in ErtcHson’s Archiv f. Naturgesch. 1846, s. 
60—66. 
