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THE AMERICAN NATURALIST. [Vol. XXXVIIl. 



Bermuda. —The account of the Bermuda Islands by Professor 

 A. E. VerrilP already issued in the Transactions of the Connecticut 

 Academy of Science \^2L^ht^x\ published by the author as a separate 

 volume. After a general description of the islands, their physiog- 

 raphy and meteorology are considered and this is followed by a 

 lengthy description of the changes in fauna and flora due to man. 

 The geology and marine zoology will appear in another volume. 

 The body of information thus brought together will be invaluable to 

 the future student of these interesting islands. 



Morgan on Evolution and Adaptation.^ — A new book on evolu- 

 tion might at first thought seem superfluous, in view of the already 

 enormous literature on this subject, but advancement in knowledge 

 calls for the presentation of fundamental principles in new lights, and 

 no one who examines this book will find it wanting in food for 

 thought. The general reader will find in it a convenient summary of 

 the older views and discussions about evolution, with extensive quota- 

 tions from the classical writings of Darwin, Weismann, and others. 

 The new point of view, which especially interests the student and 

 justifies the volume in his eyes, is that taken by Bateson (1893) in 

 his Materials for the Study of Variation, and by deVries (190 1-3) 



continuous but a discontinuous process, in which advance is made by 

 distinct steps. New species do not arise by the slow cumulation of 

 fluctuating individual variations in a particular direction, but are born 

 full fledged. A new species thus produced, which deVries calls a 

 mutation, differs from the parental species at first, perhaps, in only a 



parents, or it lacks altogether some character possessed by the par- 

 ents. It breeds true to its own distinctive character, if separated 

 from the parent species, or if not so separated may interbreed 

 freely with it. But when such interbreeding occurs the offspring fall 

 into two distinct classes, one resembling each parent form. Natura 

 selection now comes into operation to decide, not between one indi- 

 vidual and another, but between the two specific forms, that one bemg 

 favored which is best adapted to its environment, the other being 

 eliminated, or possibly being allow^ed to survive in a differejtt envi- 

 1 Verrili, A. E. The Bermuda Islands. New Haven, published by the author, 



