My life : a record of events and opinions - Wallace-online.org

HOME LIFE AND WORK 265the climate relaxing, we moved next to Croydon,chiefly in order to send our children first to a kindergarten,and then to a high school, and remained theretill May, 1881.During this period, besides my usual reviews andarticles, I prepared my address as president of theBiological Section of the British Association atGlasgow, wrote the article on " Distribution —Zoology" for the " Encyclopsedia Britannica," andprepared a volume on " Tropical Nature," which waspublished in 1878. In this work I gave a generalsketch of the climate, vegetation, and animal life of theequatorial zone of the tropics from my own observationsin both hemispheres.As soon as we were settled at Croydon, I beganto work at a volume which had been suggested tome by the necessary limitations of my " GeographicalDistribution of Animals." In that work I had, in thefirst place, dealt with the larger groups, coming downto familiesand genera, but taking no account of thevarious problems raised by the distribution of particularspecies. In the next place, I had taken littleaccount of the various islands of the globe, except asforming subregions or parts of subregions. But I hadlong seen the great interest and importance of these,and especially of Darwin's great discovery of the twoclasses into which they are naturally divided—oceanicand continental islands. I had already given lectureson this subject, and had become aware of the greatinterest attaching to them, and the great light theythrew upon the means of dispersal of animalsand plants, as well as upon the past changes, bothphysical and biological, of the earth's surface. Inthe third place, the means of dispersal and colonizationof animals is so connected with, and often