331 
little spinous, slightly curved rods (Fig. 23.c); those of the finer 
branches quite irregular, thin, scarcely branched rods (Fig. 23.d). 
Although the calcareous bodies are not of a very characteristic 
type, this species is rather unique through the exceptional number 
_ 16 — of the tentacles, 18 (17) being otherwise the lowest 
number in the species hitherto known, with the sole exception of 
Holothuria Heilprini Ives from the Gulf of Mexico^) which is stated 
to have only 10 tentacles, and the rather problematical Ånanus 
holothurioides Sluiter^), which is stated to have 13 tentacles. Of 
course, it is impossible to judge from the single specimen in hånd 
whether the number of tentacles is constantly 16 in this species; 
but this number is, in any case, so unusually low that it is very 
probably not simply a variation of the usual number 20, but really 
a specific character of this form. 
3. Cucumaria bvevidentis (Hutton). 
Thyone brevidentis. Hutton. 1872. Catalogue N. Z. Echinoderms; p. 16. 
Pentadactyla — 
Colochirus — 
Cucumaria — 
Hutton. 1878. Notes on some N. Z. Echinod. 
Trans. N. Z. Inst. XI. p. 307. 
Dendy. 1897. Observ. on the Holothurians of New 
Zealand, Journ. Linn. Soc. Zool. XXVI. p. 40. PI. 5. 
Figs. 54—61. 
Farquhar. 1898. Echinod. Fauna of N. Zealand. 
Proc. Linn. Soc. N. S. W. p. 325. 
R. Perri er. 1905. Holoth. antarctiques Mus. Paris. 
Ann. Sc. Nat. Zool. 9. Sér. I. p. 110. 
Dendy & Hindle. 1907. Add. Knowl. N. Z. Holoth. 
J. Linn. Soc. Zool. XXX. p. 99. 
1) I. E. Ives. Echinoderms from the Northern Coast of Yucatan and the 
Harbour of Vera Cruz. Proc. Acad. Nat. Sc. Philad. 1890. p. 318. 
2) C. Ph. Sluiter. Ober einige Holothurien von der West-Kuste Java’s. 
Natuurk. Tijdschr. voor Nederl. Indie. XL. 1880. 
I would suggest that the explanation of this peculiar animal is this, 
that it is a specimen which has just been dividing itself. In E. Deich- 
mann’s record of the selfdividing >4c^/nopyg'a difficilis (“On some cases 
of multiplication by fission and of coalescence in Holothurians’’. Papers 
from Dr. Th. Mortensen’s Pacific Expedition. IX. Vidd. Medd. Dansk 
Naturh. Foren. Bd. 73. 1922) it is pointed out that the radial muscles on 
the division are cut straight off, much as it is seen in Ånanus (comp. 
Fig. 2 of D e i c h m a n n’s paper with PI. III. Fig. 1 of S1 u i t e r’s paper); 
and also in Åctinopyga difficilis the posterior end of the body is com- 
pletely closed immediately after division, until a new anal opening is 
formed. 
