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Comparison with 1869
Text in this page (from paragraph 1400, sentence 100, word 44 to paragraph 1400, sentence 100, word 61) is not present in 1869
Mr. Windsor Earl has made some striking observations on this head since greatly extended by Mr. Wallace's admirable researches, in regard to the great Malay Archipelago, which is traversed near Celebes by a space of deep ocean, and this .. separates two widely distinct mammalian faunas. On either side the islands stand on a moderately shallow submarine bank, and these are inhabited by the same or by very closely allied quadrupeds. ↑ I have not as yet had time to follow up this subject in all .. quarters of the world; but as far as I have gone, the relation generally holds good. For instance, Britain is separated by a shallow channel from Europe, and the mammals are the same on both sides; and so it is with all the islands near the shores of Australia. The West Indian Islands, on the other hand, stand on a deeply submerged bank, nearly 1000 fathoms in depth, and here we find American forms, but the species and even the genera are quite distinct. As the amount of modification which animals of all kinds undergo, partly depends on the lapse of time, and as islands separated from each other or from the mainland by shallow channels are more likely to have been continuously united within a recent period than islands separated by deeper channels, we can understand how it is that a relation exists between the depth of the sea separating two mammalian faunas, and the degree of their affinity,— a relation which is quite inexplicable on the theory of independent acts of creation.
The foregoing statements in regard to the inhabitants of oceanic islands,— namely, the fewness of .. the species, with a large proportion consisting of endemic forms— the members of certain groups, and not of other groups in the same class, having been modified— the absence of certain whole orders, as of
in both of the same mammiferous species or of allied species in a more or less modified condition. Mr. Windsor Earl has made some striking observations on this head, since fully confirmed by Mr. Wallace's admirable researches, in regard to the great Malay Archipelago, which is traversed near Celebes by a space of deep ocean; and this space separates two widely distinct mammalian faunas. On either side the islands are situated on moderately deep submarine banks, and they are inhabited by closely allied or identical quadrupeds. ↑ I have not as yet had time to follow up this subject in all other quarters of the world; but as far as I have gone, the relation generally holds good. We see Britain separated by a shallow channel from Europe, and the mammals are the same on both sides; we meet with analogous facts on many islands separated by similar channels from Australia. The West Indian Islands stand on a deeply submerged bank, nearly 1000 fathoms in depth, and here we find American forms, but the species and even the genera are distinct. As the amount of modification in all cases depends to a certain degree on the lapse of time, and as during changes of level it is obvious that islands separated by shallow channels are more likely to have been continuously united within a recent period to the mainland than islands separated by deeper channels, we can understand the frequent relation between the depth of the sea and the degree of affinity of the mammalian inhabitants of islands with those of a neighbouring continent,— an inexplicable relation on the view of independent acts of creation.
All the foregoing remarks on the inhabitants of oceanic islands,— namely, the scarcity of kinds,— the richness in endemic forms in particular classes or sections of classes,— the absence of whole groups, as of