204 NATURAL SCIENCE. September. 



by Mr. Salvin, as killed on the coast of Wales, when room is given to 

 Oceanodroma crypytokucnva, on the strength of a single specimen found 

 dead in Sussex. The omission of the white-faced petrel (Pelagodyoiim 

 marina) is equally inconsistent with the insertion of the capped petrel 

 {CEstrelata hcesitafa). Generally speaking, no attempt is made to 

 describe the rarer species, though space is wasted on the plumage of 

 the house sparrow, or even on informing us that the land-rail calls 

 at night, as every schoolboy knows. Another drawback to the useful- 

 ness of the book is that the descriptions of plumage are nearly always 

 based on adult male specimens, whereas it is immature birds that 

 come most frequentl}^ into the hands of the novice. But the book is 

 an honest attempt at assisting the public to become familiar with 

 homely birds, and the author has made a fairly wise choice of the 

 space at his disposal. We trust that a second edition may be called 

 for, in which greater space could be given to explaining the changes of 

 plumage through which most species pass. Mr. Swann may be glad 

 to know that his fears for the extinction of the St. Kilda wren are 

 not likely to be realised at present. This bird has become rather 

 more numerous of late, presumably in consequence of the protection 

 afforded to it by Macleod of Macleod, and his excellent St. Kilda 

 factor, Mr. John Mackenzie. 



It is always pleasant to find an author honestly in love with his sub- 

 ject. So many books are written to suit the convenience of publishers 

 that one feels a certain relief at taking up Mr. Witchell's well-printed 

 volume, which is a book of a very different kind. Mr. Witchell is an 

 enthusiastic student of the notes of birds. He is not content to study 

 the notes of adult birds, but starts his investigations with the cries 

 of unfledged nestlings, from which he proceeds to discriminate the 

 various sounds employed by different species to convey their emotions. 

 The author is fortunately of a musical turn, and thus possesses special 

 qualifications for his self-imposed task. A certain portion of the 

 information which he has brought together is drawn from well-known 

 sources, but by far the larger part has been gained at first-hand, and 

 has the merit of being original. Perhaps the most telling chapters of 

 his work are those which discuss the influence of heredity in the per- 

 petuation of the cries of birds, and the influfence of imitation in rela- 

 tion to bird-song. Fifteen years have passed since Mr. Witchell first 

 began to study the subject. It is obvious from this circumstance that 

 the theories which he propounds have been long considered, and bear 

 some sign of concentrated thought. It is true that he has only 

 touched the border of the subject, for his observations mainly concern 

 certain species oi Passer es, which are to be found in Britain. 



Perhaps he may have opportunity of extending his observations 

 at some future date. The field of research which he has entered is a 

 wide one. But in the meantime he has succeeded in producing a 

 very agreeable book — just the sort of book to read in a country garden 

 on a summer's day, or in a punt on the Cherwell, for the matter of 

 that. If anyone wants to read a chatty, informal book about wild 

 birds, he should take in hand " The Evolution of Bird-song," for he is 

 sure to be pleased with the writer's cheerful style and happy knack of 

 registering interesting observations. 



The rising generation of naturalists are fortunate in the number 

 and quality of the works prepared for their use by the enterprise of 

 publishers. Scarcely a month passes without the announcement of 

 some fresh undertaking, intended to advance the cause of public 

 instruction in the various bypaths of zoology. Especially is this true 

 of British ornithology, which has, no doubt, an ever-increasing 



