NOTES. 281 



taline masses, therefore, the term Azoic, simply to express that, 

 tthile as far as research has hitherto gone no vestiges of living things 

 have been found in them, so also, from their nature, they seem to 

 have been formed under such accompanying conditions of intense heat 

 and fusion, that it is hopeless to attempt to find in them traces of 

 organization." Quar, Jour, of Geol. Society, i. 475. 



(12.) Ansted's Geology, i. 60. 



(13.) See De la Beche's Geological Researches. 



(14.) Mr. Homer, president of the Geological Society, in his 

 address, February, 1846, speaking on this subject, and remarking on 

 the proofs afforded by the sub-silurian rocks, of the existence at that 

 time of land and water, says, " Is it not highly improbable that this 

 sea was untenanted ?" And then he proceeds to recal the observa- 

 tions made by Professor Edward Forbes, as to a depth of sea below 

 which no life exists. The seas of that age, in the districts hitherto 

 examined, might be seas too deep to afford a proper habitat for any 

 plants or animals. 



(15.) Murchison's Geology of Eussia in Europe. 



(16.) Emmerich on the Morphology of the Trilobites. Taylor's 

 Scientific Memoirs, Aug. 1845. 



(17.) Lyell, Travels in North America. 



(18.) Murchison's Silurian System and Geology of Russia in 

 Europe. 



(19.) The head fountain of information on the early fishes is M. 

 Agassiz's Poissons Fossiles, a splendid but not readily accessible 

 book. For more popular descriptions, reference may be made to 

 " New Walks in an Old Field, by Hugh Miller," and to Jameson's 

 Journal, July and October, 1844. See also the excellent manual of 

 Professor Ansted. 



(20.) Ansted's Geology, i. 185. 



(21.) See some remarks on the grade of the cartilaginous fishes 

 in a subsequent note. 



(22.) Buffon's History of the Earth. 



(23.) Mr. Lyell tells us that remains of plants allied to the lepi- 

 dodendron, one developed on a large scale afterwards, are found in 

 America, in rocks thought to be Upper Silurian. To these are added 

 forms in the lowest Devonian strata of that country. 



