ANNOTATED LIST. 183 
Holotype: M. C. Z. No. 1062; on under side of rock, reef- flat, Mer, Murray Islands, 
Torres Strait. F. A. Potts, collector. 
This is unquestionably the most remarkable holothurian we found at Mer, and it is 
to be regretted that only a single one was seen. The dorsal surface looks so much like the 
ventral, and vice versa, that it is difficult to believe one’s eyes when dissection shows the 
attachment of the dorsal mesentery, the position of the madreporic canal, etc. The mouth, 
too, indicates the ventral surface, as it is not terminal but evidently on the lower side. 
The animal was exceedingly sluggish, and as it failed to eject any Cuvier’s organs when 
handled they were supposed to be wanting; but dissection shows them well developed. 
I know of no species to which subverta is closely related, and it will probably become the 
type of a separate genus when Holothuria is finally broken up into its component parts. 
THELENOTA? Brandt. 
Large aspidochirote holothurians, with well-marked difference between dorsal and 
ventral surfaces; dorsal with papille and pedicels; ventral with very numerous pedicels; 
on neither surface is there any indication of longitudinal series. Calcareous particles of 
body-wall of two kinds; innumerable minute oval granules 0.002 to 0.004 mm. long and 
dichotomously branched rods; the latter are not sufficiently numerous to form a distinct 
layer, but occur external to most of the granules. 
Genotype: Trepang ananas Jaeger. 
The discovery at Mer of a holothurian, as large as ananas and with very similar cal- 
careous deposits, but otherwise very different, led me to make a special study of the two 
species. I have for some time been convinced that our classification of the pedate holo- 
thurians needs complete revision, the calcareous particles of the body-wall being given far 
greater weight than hitherto as a primary indicator of relationship, and much less weight 
being given to attempted distinctions between pedicels and papillx, or to the arrangement of 
these appendages of the body-wall. Pearson (1914) has made a beginning at splitting up the 
old heterogeneous group Holothuria, but he lays more weight on the form of the calcareous 
ring, on the anal teeth, and on the ambulacral appendages than I am willing to allow 
them, and not nearly so much weight as I believe justly rests on the calcareous spicules. 
The five subgenera he proposes do not seem to me natural groups, and as he unfortunately 
fails to designate any genotypes, he has not helped very much in the elucidation of the 
subject. As he did not touch Stichopus, the present genus did not come within his field. 
The character of the calcareous deposits, quite different from any otherwise known 
in the family, seems to me sufficient reason for the recognition of this genus, but the large 
size and the arrangement of the ambulacral appendages give further warrant for such action. 
There are, however, two points with reference to the morphology of Thelenota which I 
greatly regret to have to leave undetermined. The first and more important is the number 
of tufts of gonads. All the museum material available to me is eviscerated, and I failed 
to investigate the point when fresh material was available at Mer. The holotype of 7. anax 
shows the base of a tuft on the left side of the mesentery, but there does not seem to be 
any on the right. I was accordingly inclined to put the species in Holothuria until I exam- 
ined the calcareous spicules. The best specimen of 7’. ananas in the Museum of Compara- 
tive Zoélogy has the base of a large gonad on the left side and a noticeably smaller one on 
the right. Selenka (1867) says there are 2 gonads and Semper (1868) considers that feature 
a character of the genus Stichopus, and accordingly shifts ananas to the genus where sub- 
sequent writers have left it. But I can not discover that any one has confirmed Selenka’s 
statement. It seems to me unlikely that ananas normally has 2 gonads like Stichopus, and 
1The derivation of this name (9724 = nipple+ vorov = back) is evident. It is very appropriate to the type- 
species, but much less so to the new one from Mer. 
