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ascidians; nowhere in the world have I seen anything comparable. 
Monascidians were niuch less richly developed. 
In shallow water Culcita and Oreaster occur in great quantities, 
especially the latter, from about low water mark down • to some 
10—20 Meters, so far down as can be seen through the very clear 
water by means of a water glass. About low water mark also various 
Holothurians, Årchaster iypicus and Echinaster luzonicus are fairly 
numerous, the latter very commonly infested with a beautifully 
coloured, red and white mottled Coeloplana (n. sp.), which lives 
epizoic on the starfish and, evidently, multiplies mainly through 
autotomy. - 
Coral reefs are especially richly developed around the Island 
Doe Roa and the other islands to the North (the islands to the 
South I have had no opportunity of examining). The curious faet 
that the lowest tide always oceurred during the night while I was 
staying at the islands accounts for the faet that I have paid only 
linie attention to the fauna of the reefs. I may only mention the 
occurrence in some places of numerous specimens of Åcanthaster, 
Linckia, Echinomeira and Echinostrephus. On the flåts inside the 
reef, Tripneustes gratilla was common at the south side of Doe 
Roa. A curious faet was the relative scarcity of Diadema and 
Echinothrix. On the sandy flåts inside the reef, lying dry at low 
tide, Laganum Bonani and Edwardsia's were found in great numbers 
in certain places, and, of course, the usual crabs, Mycteris and Gela- 
simus, characteristic of such localities. A peculiar feature here was 
the scarcity of animals oceurring below old coral blocks and stones 
lying on the sand. This is evidently due to the faet that the white 
coral sand is so exceedingly fine, like mud, filling out any hollow 
or crevice and leaving no free Space for the animals. This explains 
the relative scarcity of Ophiurids, which otherwise abound under 
stones and coralblocks in the low water region in tropical seas. 
In some places this fine white sand was inhabited by innumerable 
quantities of an Edwardsia sitting vertically in the sand with its ten- 
tacle Crown just above the surface, looking like small flowers in 
faet it reminded me of such places in the sand dunes along our own 
coasts, as are oceupied by the moss Polytrichum, which likewise just 
has its head peeping above the sand. 
An exceedingly beautiful sight it was to see the natives wandering 
