THE l.AGOON 195 



here and there patches of coral rocks, and here and there 

 deeper holes. The coral rocks rise almost to the surface at 

 low water, and they are for the most part of a bright yellow 

 colour, being colonies of the most abundant type of Pontes. 

 At intervals are beds of yellow branching McidrcporcB and 

 iields of green and white algee ; the whole seen through a 

 fathom or so of clear green water. Upon the sandy bottom 

 the rills of wave action are clearly to be seen, running east 

 and west — the imprints on the bottom of the Trade-driven 

 waves of the lagoon. There are, however, very many places 

 in the lagoon where the coral growth is not nearly so freely 

 scattered as that just pictured, and in areas over which the 

 foul water never exerted its baneful influences are stretches of 

 white coral sand, where a coral mass will have no neighbour 

 nearer than one some fifty yards away. 



From the southern shallows the lagoon deepens towards 

 the north, where it becomes a basin with an average depth of 

 from four to five fathoms. Even in this deeper part, however, 

 there are many spots where the growing masses of coral rise 

 to within a few inches of the surface at low water ; — some are 

 even normally exposed at all low tides. One such mass rises 

 from Dymoke shoal in the northern basin, opposite Pulu Selma, 

 and this rock — known to the natives as Batu Dua, or " The 

 number two rock " — is exposed for some two feet at most low 

 tides. The transition from the shallow portion of the lagoon 

 to the deeper portion is very easily seen in the colour of the 

 water, and at places the line of demarkation is very sharply 

 cut. The clear green water of the shallow sand- covered 

 portion passes, often very abruptly, into a very beautiful blue, 

 — a clear wonderful blue, which can never be described or made 

 real. The entrance into the lagoon is between Pulu Luar and 

 Pulu Tikus, and here ships may be safely navigated by one 

 knowing the locality. A good anchorage stretches in front of 

 Pulu Tikus with from three to eleven fathoms of water. It is 

 possible for vessels of shallow draught to enter the lagoon be- 

 tween Pulu Luar and Pulu Panjang, both to the north and to 

 the south of Turk Eeef {Batu Satu, " The number one rock "), 



