WIDE DIFFUSION OF SPECIES IN ANCIENT DEPOSITS. 



583 



through long epochs ; while others of a higher structure, passed away in compara- 

 tively short periods. 



There is yet, however, a phenomenon of the highest importance, connected with the 

 distribution of organic remains in the older strata, which has not been adverted to ; 

 namely, that the same forms of crustaceans, mollusks and corals, are said to be found 

 in rocks of the same age, not only in England, Norway, Russia, and various parts of 

 Europe, but also in Southern Africa, and even at the Falkland Islands, the very anti- 

 podes of Britain. This fact accords, indeed, with what has been ascertained concerning 

 the wide range of animal remains in deposits equivalent to our oolite and lias ; for in the 

 Himalaya Mountains, at Fernando Po, in the region north of the Cape of Good Hope, 

 and in the Run of Cutch and other parts of Hindostan, fossils have been discovered, 

 which, as far as the English naturalists who have seen them can determine, are un- 

 distinguishable from certain oolite and lias fossils of Europe 1 . 



Another remarkable fact illustrating this point of inquiry is, that although the older 



fossiliferous strata often contain vast quantities of organic remains, the number of species 



is much smaller than in more recent deposits. Judging from my own labours, I can 



affirm, that after seven years devoted to this inquiry, the number of species collected 



at the end of four years was little less than the aggregate now published. The above 



resemblance, therefore, (if not identity) of certain forms, out of this number, which are 



found in opposite hemispheres, is the more surprising. 



» 



1 The largest collection of fossils from the Himalaya, with which I am acquainted, was brought home by- 

 Lady Sarah Amherst, and being examined by Mr. James Sowerby was found to contain several Ammonites 

 undistinguishable from our English species of the lias. 



The specimens from Fernando Po and the opposite coast of Africa were collected by Capt. Sir C. Bullen, R.N., 

 and when placed on the table of the Geological Society every person present who was conversant with lias fossils, 

 thought these samples had been merely sent up from Lyme Regis (Ammonites communis, #c). 



The fossils from the Orange River, six hundred miles north-east of Cape Town, including Astarte orbicularis 

 and Gervillia aviculoides of the green sand, and Trigonia clavellata of the oolite, were collected by Dr. Smith, the 

 enterprising explorer of Southern Africa. 



The fossils collected by Captain Smee in the Run of Cutch, are very numerous, and several of them, such 

 as Gryphcea dilatata, Trigonia costata, fyc, are identical with English oolitic species. (See Proceedings of the 

 Geological Society, vol. ii. p. 77.) 



The fossils from the Falkland Islands were discovered by Mr. C. Darwin, and they appear to me to belong 

 to the Lower Silurian Rocks. 



It is well known that certain species of Trilobites are common to the older rocks of North America and 

 various parts of Europe ; the same fact has been since established repecting South Africa, through the labours 

 of Dr. Smith above alluded to. At Cedarberg, one hundred and fifty miles north of Cape Town, he found 

 an assemblage of fossils evidently composing an Upper Silurian group, in which are some species which mark 

 the passage from the Old Red Sandstone to the Ludlow Rocks and others which are abundant at Ludlow and 

 Wenlock. These fossils were first forwarded to me by my distinguished friend Sir John Herschel, and among 

 them we observe the Homanolotus Herschelii (Nob.), PI. 7 bis. f. 2., with Calymene Blumenbachii and other tri- 

 lobites, associated with casts of shells undistinguishable from the following species figured in this work. Cu- 

 cullcea ovata, Leptcena lata ?, Orbicula rugata, Nucula, Turbo, Turritella and Conularia quadrisulcata. 



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