IN THE MUD OF THE LEVANT. 121 



Chalk rocks. How much more so when these are 

 numerous, and such as form large masses. The 

 size appears to be of no importance, as the small 

 organisms have already been shewn to agree with 

 the large, with regard to the effect of external 

 influences upon them."* 



As regards the higher animals, the first part 

 of this paragraph is doubtless correct ; but the 

 force of the argument is weakened, if not 

 destroyed, when it is applied to the Foraminifera 

 and other microscopic creatures. The small 

 organisms do not agree with the large, with 

 regard to the effect of external influences upon 

 them. With reference to climate, enough has been 

 said to prove, that they neither follow parallels 

 of latitude, nor isothermal lines ; and as regards 

 another condition, Professor Forbes has shewn 

 that Foraminifera occur in the sea, at a depth 

 of one hundred fathoms, when the higher forms 

 of animals and plants cease to exist ;■}" also, 

 Alcide D'Orbigny informs us, that, opposite 

 Cape Horn, at a depth of one hundred and 

 sixty metres, (about eighty-seven fathoms,) the 



* Edin. New Phil. Journal. Vol. xxxiv. p. 258. 

 t On the Light thrown on Geology by Sub-marine Re- 

 searches. Edin. New Phil. Journal. Vol. xxxvi. p. 319. 

 n 



