30 JANUARY 1948, Page 16

London as Sanctuary

Even London cultivates county pride, as witness a book now in prepara- tion "on county history lines" dealing with the avifauna of the more typical habitats, migration, and the influence of urbanisation on birds and other animals. The Journal of the London Natural History Society is among the richest of all published research into ecology, in spite of urbanisation. A most suggestive example is the association of hornets— numerous in London environs—with the strange alcoholic fermentation of the bark of oaks (chiefly pedunculate oaks) and birches. The hornets infest the trees and so increase their own favourite food supply! Of course, " London " is used in a. very wide sense and includes reservoirs and parks and even spinneys that can hardly be regarded as urban, but central London is astonishingly rich in denizens of various genera, especially birds which seem to be progressively colonising central parks and ponds. The hornets are the more interesting because smoke and noise and people appear to be more repellent of insects than of birds. A rare dragon-fly or two has been observed in the suburbs, but even the artificial breeding of butterflies has failed in, for example, Battersea Park. They are as allergic, as doctors would say, to London as is every form of lichen.