MUD DEPOSITS. 195 



becomes partially isolated, and the deep-sea- 

 creatures living in it, owing to the change of 

 conditions, are killed off. This was found to be 

 the case with the little basin of Simbolu, itself 

 thirty fathoms deep, whilst the entrance was 

 not so much as seven. Here the centre was 

 filled with mud, in which we found imbedded 

 masses of wood, and even quantities of leaves, 

 borne into the basin by torrents during the rainy 

 season. 



The mud of such basins, and that of confined 

 and shallow parts of the bay and gulph, is in- 

 variably dark-coloured in the Lycian sea. It 

 might be termed blue mud ; in most places it 

 is very prolific in organic contents, but where 

 the walls of the bay are almost entirely com- 

 posed of serpentine — as in several places on 

 the coast of Caria — there is a remarkable de- 

 ficiency of animal contents, especially of tes- 

 taceous mollusca. The muddy deposits from the 

 deep sea is usually, almost invariably, of a pale 

 yellow colour, and when dried nearly white. The 

 region of this yellow mud is the sea bed below 

 eighty fathoms, more commonly below one hun- 

 dred. From that depth, down as deep as we 

 were enabled by means of the dredge to explore, 



o 2 



