32 THE ECHINODERMS OF TORRES STRAIT. 
Culcita novaeeguinea. 
Miller and Troschel. 1842. Sys. Ast., p. 38. 
(Plate 5, Figure 1 ) 
It is a notable fact that no Culcitas were taken in Torres Strait by the Challenger, 
or the Alert, or by Semon. We found them common at Erub and at Mer, and there is a 
specimen in the Museum of Comparative Zodlogy, from Warrior Reef. Gray’s type of 
C. pentangularis is said to have come from the reef at Umaga (Keat’s Island), which is 
about half-way between Warrior Reef and Erub. All of the specimens I have seen from 
this eastern end of the Torres Strait region are noveguinee and I have no doubt that pent- 
angularis is the same thing. The species has a very wide range, from Mozambique to the 
Society Islands, and northward to the Andamans and to Kagoshima, Japan. 
Few genera of star-fishes have given rise to more discussion on the specific limits 
of the forms they contain than has Culcita. Several ‘‘revisions”’ of the genus have been 
published, but the species are so variable and the appearance of museum material is so 
dependent on methods of killing and preserving that we are still very much in the dark 
as to the number of valid species. The latest reviser, Goto (1914), admits 7 species, one 
of which has 2 named varieties, and another 4. Of the 7 species, however, borealis Sussbach 
and Breckner (1910) is so obviously not a Culcita, or even one of the family Oreasteride, 
that it is odd that Goto should have admitted it to his key. Of the other 6, grex and coriacea 
are two of Miller and Troschel’s species, which are rare and still little known. I have 
seen neither. A third is Perrier’s remarkable C. veneris, from the island of St. Paul and 
recorded by Bell from the coast of South Africa also. A fourth species, C. niassensis Sluiter 
(1895) is apparently a Choriaster, if not indeed Ch. granulatus Liitken. There are then left 
only noveguinee, with its varieties, plana, typica, arenosa, and acutispinosa; and schmide- 
liana, with varieties ceylonica and africana. There is not sufficient material at hand for 
me to satisfy myself as to the status of these forms, but I am sure that the Culcita found 
at the Hawaiian Islands, and of which I found an excellent living specimen at Hilo, is 
absolutely different from the species found at Erub and Mer. Since this Hawaiian Island 
form is the original of arenosa, I can not admit it merely as a variety of noveguinee. Several 
writers have intimated that noveguinee and schmideliana intergrade, but so far as my 
experience goes each seems a valid species, although each is very variable. 
At Erub and Mer adult Culcitas occurred on the reef flats on open sandy bottom, 
where the water even at low tide was 2 feet or more in depth. They were of course abso- 
lutely inert, but on being taken from the water they contracted more or less markedly. 
If placed in a basin, they expelled water from the anal opening with sufficient force to make 
a jet 1 to 2 inches high. The contraction and consequent ejection of water led of course 
to a considerable decrease in bulk, but there was never any tendency to flatten out, the 
height of the animal in proportion to its horizontal diameter undergoing little change. 
Even when thus contracted a Culcita is not so rigid as it appears. One morning while 
wading ashore after several hours of collecting on the reef flat at Mer, I came upon a Culcita, 
which I wished to take back to the laboratory. My bucket was well filled with brittle- 
stars and comatulids and I felt sure they would be badly damaged if I put this heavy 
Culcita among them. Deciding to carry it in my water-glass, I found that it was too big 
to go in, so laying it on the open end of that instrument, I pushed on towards the beach. 
A few minutes later there came a crash and I found that the Culcita, whose horizontal 
diameter had seemed so much greater than that of the water-glass, had bent up the ends 
of its rays to such a degree that it had fallen straight down through the water-glass, taking 
the invaluable pane with it! 
The diversity shown by adult Culcitas in the character of the dorsal surface, as well 
as in the coloration, is very considerable. In some specimens the small tubercles are scat- 
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