404 . Recent Literature. [juiy 



tioned. Mr. Eagle Clarke attributes the origin of the migration of birds 

 to the failure of the food supplj' on the approach of cold, but adds that 

 today " the migratory habit has become part and parcel of their lives, 

 through countless ages of practice." He considers, as Dr. Watson's experi- 

 ments have proved, that migration is accomplished " through a special 

 sense of direction unconsciously exercised " or as Professor Newton phrased 

 it by " inherited but unconscious experience." He points out the familiar 

 routes across the Mediterranean all supposed to be due to following the 

 lines of former land bridges, but makes no mention of the route across the 

 Gulf of Mexico which Prof. Cooke seems to have pretty well proven and 

 which certainly follows no such line, crossing as it does the deepest portion 

 of the Gulf. The Chapters covering bird migration in the British Isles 

 are full of interest and replete with detailed data. These chapter headings 

 are as follows: III. The British Isles and their Migratory Birds; IV. The 

 Geographical Aspects of British Bird-Migration; V. Round the Year 

 among the British Migratory Birds: Spring; VI. Autumn; VII. Winter; 

 VIII. Weather Influences: The Meteorology of Bird-Migration; IX. 

 Migration of the Swallow; X. Fieldfare; XL Wagtail; XII. Song Thrush; 

 XIII. Skylark; XIV. Lapwing; XV. Starting; XVI. Rook. 



Most interesting is the account of the east and west migration into 

 England from the valleys of the Rhine, Maas and Schelde. The birds 

 actually fly northeast from the highlands bordering the Alps on the north, 

 down the river valle3's and across to southern England where the winter 

 chmate is milder ; so that they winter in a higher latitude than that in which 

 they nest. In the case of the Rookt; and certain other species, Mr. Eagle 

 Clarke states that part of those which breed in England arrive from the 

 south in February and March, while at the same time, those of Central 

 Europe which wintered in southern England are leaving that country for 

 their breeding grounds on the headwaters of the Rhine. 



Those who keep yearly records of the arrival of birds in America will 

 be interested in comparing their lists with those which our author has 

 prepared for the British ' harbingers of spring.' 



The last ten chapters deal with Mr. Eagle Clarke's sojourns on light-ships, 

 lighthouses and remote islands on the British and Scottish coasts, while 

 pursuing his studies. These are as follows: XVII. A Month on the Eddy- 

 stone; XVIII. A Month on the Kentish Knock Lightship; XIX. Fair 

 Isle, the British Heligoland; XX. A Year with the Migratory Birds at 

 Fair Isle; XXI. The Birds of Fair Isle; XXII. Bird Migration at St. 

 Kilda; XXIII. The Birds of St. Kilda; XXIV- The Flannan Isles; XXV. 

 Sule Skerry; XXVI. Isle of Ushant and Channel Islands. These chapters 

 furnish most interesting reading and a wealth of information. The birds 

 of many of the localities had never been previously studied so that the lists 

 and observations have an interest in addition to that which attaches to 

 the migratory movements. 



Mr. Eagle Clarke's ' Studies ' will take their place among the note- 

 worthy contributions to the study of Bird Migration, and we can recom- 



