4 APRIL 1931, Page 12

BLACKBIRD AND BLACKTHORN.

Those engaging men of science, if theirs is a science, who call themselves phenologists, are making a special plea (through the B.B.C. and elsewhere) for exact data about phenomena—to adhere 3 to their Greek preferenees--in several departments of natural history. It is a pretty science, because it depends on open-air observation and demands an acquaintance with many different sorts of things. They are stressing for the moment information about the date when the blackbird builds and when the blackthorn flowers. They seem

to be a little nigriphil, but the blackthorn appears to be a key plant ; and for all I know the blackbird may be a key animal. Now the idea of phenology is that you may discover, on behalf both of the meteorologist and the farmer, useful correlations. Such and such a date of building or flowering may imply such and such successional weather and suggest the timing of such and such farming operations. The moral is the moral of Tennyson's " flower in the crannied wall." The processes of nature are inter-related. If we can interpret what is obvious we can discover what is obscure. The B.B.C. have, therefore, promised to deliver forms for amateur observers here, there or anywhere to fill up.