TRANSACTIONS OF SECTION C. 



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Vfore you my quotations of the most authoritalivo writers havo b«.'en made lena 

 fir tlie purpose of showing' reverence than of expressing scepticism. My reasoa 

 fir cftUiiiff attention to Professor Huxley's views is different. I entirely agree 

 withtliem; but there is, I think, snmetliinjr to be added to them. There is, 1 

 l>'Iii've, an additional distinction between land and murine faunas that requires 

 uotice, and this distinction is one of very preat importance and interest. It 

 appears to me that at the present day the difl'erence between the land-faunas of 

 •litier^nt parts of tlio world is so vastly prcater tlian tlint between the marine 

 t'iuinas, tiiat if both were found fossilised, wliilst tliere would be but little dilficulty 

 111 rt'cofrnisinpr different marine deposits as of like nprt* from tlitnr organic remains, 

 t-^rrestriul and fresh-water beds would in nil proluibility be referred to widely 

 ditleriupr epochs, and that some would be more pro))ably classed with those of a past 

 iieriod tiian with others of tlie present time. 



1 had proposed to enter at some leng-th into this subject, and to attempt a 

 .sketch of the present state of our knowledge concerninf,' the distribution of terres- 

 trial and marine faunas and floras. Hut I found that it was impossible to do 

 justice to the question without making this address far longer than is desirable, 

 and I have already taken up more time than I ought to have done. I can there- 

 fore only treat the subjwts very briefly. 



As you are doubtless aware, the most important work upon the distribution of 

 terrestrial animals yet published is that of Mr. Wallace. lie divides the earth's 

 surraoo into six regions — Paloearctic, Ethiopian, Oriental, Australian, Neotropical, 

 and Nearctic. Some naturalists, with w^hom I am disposed to agree, consider 

 Madagascar and the adjacent islands a seventh region, and it is possible that one 

 or two other additions migiit be made. 



These regions are essentially founded on the distribution of vertebrata, 

 especially mammals and birds, and the following table, taken from Wallace's lists, 

 shows the percentage of peculiar families of vertebrata and peculiar genera of 

 mammalia in each region, mammalia being selected as more characteristic thau 

 birds and better known than reptiles, amphibians, or fishes : — 



The marine mammals and reptiles are too few in number to be compared with 

 the land-fauna, but whales, porpoises, seals, sirenians, turtles', and sea-snakes are 

 for the most part widely difiused. Tiie best class of thf vertebrata for com])arisoti 

 is that of the fishes, and some details taken by AN'allace from Giinther's ' British 

 Museum Catalogue' are very important. The whole class is divided into 110 

 families, of which 20 are exclusively confined to fresh water, whilst 80 are typically 

 marine. Of these 80 no less than CO are universally, or almost universally, dis- 

 tributed, whilst many others have a very wide ran;:e. Four families are con- 

 fined to the Atlantic and 13 to the Pacific Ocean, whilst n few more are 

 exclusively southern or northern. About CJ are found in both the Atlantic and 

 Pacific. 



Now, of the 29 fresh-water fnmilios lo, or more than one-half, are confined 

 each to a single regif)n, i) are found eacli in two regions, 2 in lln-ee regions, and 

 the same number in four: one only (rvyj/vV/Zr/^) is found in five regions, whilst 

 not one is met with in all six. It is impos.Mble to conceive a greater contrast: 

 00 murine families, or Oi'O per cent., have a world-wide distribution, whilst not a 



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