FRYER— FORMATION OF ALDABRA, ETC. 441 



DESCRIPTION OF PLATES. 



Plate 22. 

 Map of Aldabra Island. (Reproduced by permission of the Cambridge Philosophical Society.) 



Plate 23. Aldabra. 



Fig. 1. Sea cliffs and reef on the north coast near Passe Houareau. Note overhanging cliffs and 



large fallen mass of rock due to sea erosion. On the top of the cliffs is a Casuarina tree and 



a belt of Pemphis and Scwvola. 

 Fig. 2. Portion of the cliff- face (to seaward) of Malabar Island to show fossil corals in position of 



growth. The cliff at this point measures 12 feet in height. On the top of the cliffs is the beginning 



of the Pemphis bush. 



Plate 24. Aldabra. 



Fig. 1. Sea cliffs to the south of Main Island (the end of the Takamaka section). Note the sloping 

 buttressed cliffs and the " shore zone " piled with sand and carrying a short dune grass. 



Fig. 2. Portion of the sea cliff of Picard Island to show the composition of the rock. The coral colonies 

 are all in same relative positions as when alive. 



Plate 25. Aldabra. 



Fig. 1. " Champignon country " on Picard Island. The rock is metamorphosed coral limestone pitted 



and denuded by rain-water. In the distance is the edge of the bush. 

 Fig. 2. "Platin country" on Picard Island. The rock consists of a conglomerate of worn coral fragments 



and reef debris. The shallow depressions are caused by rain-water denudation. 

 Fig. 3. A typical example of a small island or large rock in the lagoon. The birds on the rock are 



Noddy Terns (Anous leucocapillus). 

 Fig. 4. View in Lagoon showing island masses off the shore of the land-rim of the atoll. 



Plate 26. Aldabra. 



Fig. 1. A natural pit in the rock on Picard Island. It is in subterranean connection with the lagoon 



(distant \ mile) and is filled with tidally fluctuating water. The pit is rapidly becoming larger 



owing to erosion. 

 Fig. 2. " Basin Cabris " on Picard Island. It forms a small lake with a subterranean connection to 



the lagoon, its waters being tidal. 

 Fig. 3. Camp Frigate on Malabar Island. The mangrove swamp has penetrated through the land-rim 



and is here seen arriving at the sea. After the lagoon has washed away a little more land a tidal 



current will be enabled to sweep through and cut a fresh pass. 

 Fig. 4. One of the Western Channels (from the lagoon looking seawards). The lagoon has cut a passage 



through the land-rim to the sea but has not yet removed two small islands. These are being cut 



away by current erosion (as is shown by their overhanging cliffs) and in time an open pass will be 



formed. 



Plate 27. Aldabra. 



Fig. 1. Esprit Island, showing its wall of shell rock (see pp. 401, 402) with a Banyan tree (Ficus sp.?) to 



the left. 

 Fig. 2. Esprit Island : cliffs of south shore showing pinuacles of shell rock with phosphatic rock below. 



