zoological, discussion of those proposed by various authors, 61
zoological, proportionate richness of, 64
temperate and tropical, well marked in northern hemisphere, 65
and zones, table of, 66
comparative richness of, 81
and sub-regions, table of, 81
order of succession of the, 173
Representative species, 4
Reptiles, means of dispersal of, 28
classification of, 98