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over the rock one sees them retracting into their holes, quick as 
lightning, and it is only on approaching very cautiously that one 
succeeds in observing them distinctly. When standing quite still for 
some minutes one may see them come out again, head and fore- 
body, from their holes, and in this way it was even possible to 
take a photo of them. On the other hånd, I found it quite impos- 
sible to secure a complete specimen, the rock being much too hard 
to be cut to pieces without crushing the worras, which appear to 
be of a very considerable length. I had to content myself with cut- 
ting off the foreend of some specimens, when they had extended 
themselves over the rock. 
On the sandy parts of the flat, in such places where a thin 
layer of water remains at low tide, innumerable specimens of the 
starfish Årchasier typicus are crawling about or lie buried in the 
sand, a star figure showing the place of their hiding. In the muddy 
parts the flat Scutellid Årachnoides placenta is the main inhabitant, 
while in the areas covered with sea grass (Thalassia testudinum) 
meterlong, greyish-brown, warty Synapta’s and a red Oreaster are 
the dominant forms. Numbers of fishes also occur here, among 
which Ophichthys colubrinus is the most sensational, affording one 
of the most perfect cases of mimicry; it resembles the sea-snake 
Platurus colubrinus (Schneid.) (which also occurs here) so completely 
in colour and shape that even an expert ichthyologist would hardly 
venture to say, except on a doser inspection, whether it is the fish 
or the snake he has before him. 
Places of sandy bottom, which become quite dry at low tide, are 
inhabited by a large Enteropneust, its huge sandy excrements show¬ 
ing the spot, where it may be dug out. Also various forms of 
Sipunculids, Annelids and Molluscs may be found here, as also 
Lingula and Amphiurids, whereas I was disappointed in not finding 
here any of the smaller forms of Synaptids otherwise usually living 
in such places. Numerous crabs (Gelasimus and Mycteris) also occur 
in such localities, strewing their characteristic sand-pellets over 
the surface. Upon the whole, an almost endless number of forms 
occur here, offering a rich harvest to the collector and a most 
fascinating study to the naturalist, who takes an interest in marine 
ecology. 
The coral “gardens”, of which Ambon boasts as a special attraction. 
