that carbonic acid (Co2), the principal food of plants, cannot be decomposed under a lower temperature than 2,500° Fah.; but plants, by the aid of sunlight, easily decompose and utilize it, and to plant-life the presence of abundant light rays is absolutely indispensable; or, as Fiske eloquently expresses it, “The slower undulations penetrating the soil set in motion the atoms of the rootlet, and enable them to shake hydrogen atoms out of equilibrium with the oxygen atoms which cluster about them in the compound molecules of the water. The swifter undulations are arrested by the leaves, where they communicate their motor energy to the atoms of chlorophyll, and thus enable them to dislodge adjacent atoms of carbon from the carbonic acid in which they are suspended.” These changes, so poetically described, are greater in New Zealand than in England, and in the internal economy of each individual certain similar changes obtain. The increased heat causes a diminution in the quantity of carbonic acid excreted by each human individual. Vierordt proved that every rise in temperature of 10° Fah. caused the individual to exhale two cubic inches less per minute. According to this scale, the Englishman who at home would excrete eight ounces of carbon in 24 hours by his lungs, would in New Zealand exhale only about seven ounces;—this means that the man in New Zealand would eat less, and would do less work, than when at home. A popular belief asserts that men can adapt themselves to any climate, and can flourish there. This belief is wrong. It is true that the genus homo can endure a cold in Siberia of 109° Fah., or 120° Fah. (i.e., 150° of frost), or, in a Persian desert, a heat of 179° Fah., a difference of 300°; but varieties, or species, of man will not bear transplanting to markedly opposite climates. The Esquimaux and the Fantees would soon die if they changed places. A scanty remnant of the original colony might survive the change for a few years, but the majority would soon perish; and probably, after one or two generations at most, the race would become extinct. Even with less extremes similar results obtain: Englishmen in India, Sierra Leone, and in Guiana die fast, and but for a constant stream of immigration would, in two or three generations, become extinct. So, too, the Dutch in Java are all immigrants from Holland. The climate of New York is fatal to the tropical bred negro. Of course, the climate of New Zealand is nothing like as hot as in some of these countries, yet the greater intensity and directness of the solar rays, as compared with those in Great Britain, does produce certain marked changes. Experiments very numerous, and conducted on large numbers of persons, prove that all our functions are carried on more quickly in summer than in winter; men and animals gain weight in spring and summer, and lose it in autumn and winter; the hair, too, grows more quickly in summer