ABSTRACT
In the last two studies (XI and XII), we have illustrated one of the large facts of life—the way in which living creatures tend to fill up every corner of earth and sea. Thus there are many plants and animals in the barren grounds or Arctic tundra, snow-covered and frost-bound for eight or nine months of the year; there is a very distinct fauna and flora of the high Alps, where snow voles and blue gentians are at home; there is a dense population of animals in the unbroken night and endless winter of the Deep Sea. But another great fact, the study of which is often called Phenology, is the waxing and waning of life as the earth moves round the sun. In other words, there is a march of the seasons, especially well-marked in temperate countries; and the seasons do to some extent hold living creatures in their grasp. T<sc>he</sc> B<sc>iological</sc> P<sc>rism</sc>. https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9780203705568/ddd3fccb-b02e-4ec3-bb55-b316faa49ca8/content/fig_13.tif"/>
The organism must always be studied in its relations to its surroundings or environment. It acts on its surroundings and is acted on by them. The prism is drawn uncompleted, to suggest that all three sides are changing. It is not the same organism, or the same environment, or the same functioning, all the time.
