288 EAMBLBS OP A NATURALIST. [Oh. XVII. 



the appearance into dense crowds of thousands of white 

 birds, whose general movement gave the rocks a quivering 

 aspect, as when the rarefied air ascends from a heated 

 surface. 



The shores of Johore, bordering on the Straits, are every- 

 where thickly wooded, the jungle coming down to the water's 

 edge. The low banks are seldom reheved by a hill, or any- 

 thing which serves to distinguish one part from another, 

 and not a habitation is anywhere visible. I one day landed 

 upon the beach at South Point, and spent some hours in 

 exploring. The coast was rocky, with reefs of porphyritic 

 stone containing large crystals of albite; and a shelving, 

 sandy shore extended so close to the edge of the jungle, 

 that only a yard or two was left dry at high water. In the 

 jungle, Cycads and screw-pines abounded ; and I fancied I 

 could trace the tracks of large animals, which my imagina- 

 tion helped me to believe were tigers, upon the higher parts 

 of the sand. Butterflies of the same type as those I had 

 observed at Labuan were pretty numerous. 



A curious little Crab is common upon the sandy beaches 

 everywhere on these coasts. I observed it abundantly at 

 Labuan, and at Singapore and Johore, and other places, 

 where, immediately after the tide has gone down, the smooth 

 beach is covered with loose, powdery sand and holes of 

 various sizes, from such as would admit a small pea to 

 those big enough for a large filbert, but usually of the former 

 dimensions. A closer examination showed that little ra- 

 diating paths converged among the litter of sand to each 

 hole, and that the sand itself was in minute balls or concre- 

 tions of a size proportionate to the calibre of the holes. The 

 rapidity with which the shore was covered with myriads of 

 such concretions was very surprising, as at first there ap- 



