Welsh Journals

Cardigan, with a Bank Vole (Clethrionomys glareolus) in its jaws, on 12th Feb. 1962 (P.J.P.). Polecat (Mustela putorius). Cards. A large adult male, trapped on 7th Jan. 1962 after killing poultry, was received alive from Pengraig farm, near Tre- garon, but it soon died. (P.J.P.). The Grey Squirrel invasion in 1961 Some thirty correspondents have written to confirm the now fairly well-known invasion of West Wales by the Grey Squirrel (Sciurus carolinensis) in the summer and autumn of 1961. Even The Listener gave five columns to its antics in Swansea, Aberystwyth and elsewhere following a report in Radio Newsreel" and the Swansea Evening Post gave prominence to news and letters about its presence and numbers in September. But it has reached the entire sea coast of Pembrokeshire and Cardiganshire, too, appearing in treeless areas (St. Davids, 11th October, Mrs. M. BARNES Aber- castle, 1st October, R. C. GREGORY-SMITH). P. M. MILES considers it has now completed its conquest of West Wales, having bred at Trawscoed, near Aberystwyth, for some years. It has settled in all largish woods in the extreme west as at Orielton (140 acres) and Benton (300 acres), in Pembrokeshire and along the Teifi valley to Cardigan town, Aberaeron and Aberystwyth. It has been met with on mountains above the tree-line, and in rabbit burrows by the sea, during its late autumn dispersal. The Ministry of Agriculture supplies a list of some 40 records for Cardiganshire, June to December, and 2 from Merionethshire. Apparently the migrants observed in open, more or less treeless, country did not stop for more than a few hours, if as much, and the movement was not observed to continue in treeless areas after the end of the year (except at Solva, Pembs., where Grey Squirrels settled in a granary during the winter, on the coast farm of Llan- unwas, which has a small wood). R. M. LOCKLEY. BOOK REVIEWS Bird Song. By W. H. THORPE. (Cambridge Monographs in Experimental Biology, No. 12.) Cambridge University Press. 1961. 20s. Why do birds sing ? As a territorial proclamation, an actual means of defence, a substitute for fighting, or for the pleasure of exercising the syrinx (as their vocal apparatus is termed) ? Apparently they sing for one or some of these reasons, Dr. Thorpe informs us. One of the functions of the complexity in song is to