APPENDIX. 245 



there are no extensive coral-reefs on any part of the coasts 

 of Indict^ except on the low promontory of Madura (as 

 already mentioned) in front of Ceylon. 



Red Sea. — My information is chiefly derived from the 

 admirable charts published by the East India Company in 

 1836, from personal communication with Capt. Moresby, 

 one of the surveyors, and from the excellent memoir, 

 Tiber die Natur der Corallen-Bdnken des Rothen Meeres, 

 by Ehrenberg. The plains immediately bordering the Red 

 Sea seem chiefly to consist of a sedimentary formation of 

 the newer tertiary period. The shore is, with the exception 

 of a few parts, fringed by coral-reefs. The water is generally 

 profoundly deep close to the shore ; but this fact, which 

 has attracted the attention of most voyagers, seems to 

 have no necessary connection with the presence of reefs ; 

 for Capt. Moresby particularly observed to me, that, in 

 lat. 24 io' on the eastern side, there is a piece of 

 coast, with very deep water close to it, without any reefs, 

 but not differing in other respects from the usual nature of 

 the coast-line. The most remarkable feature in the Red Sea 

 is the chain of submerged banks, reefs, and islands, lying 

 some way from the shore, chiefly on the eastern side; the 

 space within being deep enough to admit a safe navigation 

 in small vessels. The banks are generally of an oval form, 

 and some miles in width; but some of them are very long in 

 proportion to their width. Capt. Moresby informs me that 

 any one, who had not made actual plans of them, would be 

 apt to think that they were much more elongated than they 

 really are. Many of them rise to the surface, but the 

 greater number lie from 5 to 30 fathoms beneath it, with 

 irregular soundings on them. They consist of sand and 

 living coral; coral on most of them, according to Capt. 

 Moresby, covering the greater part of their surface. They 



