Oct. 1 8, 1888] 



NATURE 



#7 



cases just mentioned the labour was well spent, but in 

 others it is practically thrown away in the attempt to 

 pierce a labyrinth the clue to which can be found only by 

 mathematics. Prof. J. J. Thomson's book ought to be 

 carefully studied by all physicists, and especially investi- 

 gators who have discovered what they believe to be a new 

 fact. In many cases it will suggest possible explanations 

 which may prevent long and wearisome groping in the 

 dark. 



The author is to be warmly congratulated on his work, 

 which is an achievement of a high order, and which will 

 add to his already great reputation as a mathematical 

 physicist. 



RECENT WORKS ON ORNITHOLOGY. 



Argentine Ornithology. By P. L. Sclater, M.A., F.R.S., 

 &c, and W. H. Hudson, C.M.Z.S. Vol. I., pp. i.-xvi., 

 1-208, pis. i.-x. (London : R. H. Porter, 1888.) 



British Birds : Key List. By Lieut.-Colonel L. Howard 

 Irby. Pp. 1-58. (London: R. H. Porter, 1888.) 



Biidsnesting and Bird-skinning : A Complete Description 

 0/ the Nests and Eggs of Birds which breed in Britain. 

 By Edward Newman. Second Edition. Revised and 

 re-written, with directions for their collection and 

 preservation ; and a chapter on Bird-skinning, &c. 

 By Miller Christy. Pp. i.-xii., 1-138. (London: T. 

 Fisher Unwin, 1888.) 



DR. SCLATER AND MR. HUDSON have combined 

 their forces to produce one of the best books ever 

 written on South American ornithology. Each is a 

 master of his own portion of the subject, for no one is 

 better acquainted with neotropical ornithology than Dr. 

 Sclater, and Mr. Hudson has been known for many years 

 as one of the best living observers of the habits of birds 

 in the field. The scheme of the book, therefore, leaves 

 nothing to be desired, and the whole of the "get-up," as 

 regards paper, print, and illustrations (the latter a matter 

 of course when Mr. Keulemans is the artist), is about as 

 good as it is possible to be, and reflects the greatest 

 credit on the publisher. 



One of the most interesting features of the work will 

 doubtless be the introduction, which will appear in the 

 second volume, when it will be possible to form some 

 accurate notion of the relations of the avifauna of the 

 Argentine Republic with that of the neighbouring States, 

 a^comparison which will doubtless be of importance to 

 all naturalists who are interested in the somewhat com- 

 plicated natural areas of the neotropical region. At 

 present the genera and species peculiar to the region 

 treated of by the authors seem to be few in number, and 

 they would appear to be limited to the more western 

 portions of the country, especially the district of Tucuman. 



It would be easy to give many extracts from Mr. 

 Hudson's charming writings on the habits of the birds, 

 with the life-history of many of which he is as familiar as 

 we are in England with that of many of our British birds, 

 while his travels have enabled him in many instances to 

 give an account of species both in their summer and 

 winter homes. To any naturalist visiting Argentina this 

 book will be of the highest value, the descriptions given 

 by Dr. Sclater being short and concise, but sufficient for 

 the identification of species, while he is to be congratulated 



also on the success with which he has contrived to 

 attach an English name to each bird. Everyone who 

 has tried to do this, when writing on exotic birds, knows 

 how difficult it is to invent English titles for species 

 which have no counterpart in European nomenclature ; 

 and we must acknowledge that the names are a great 

 improvement on some of the zoology "as she is taught" 

 at our Zoological Gardens. Should some of the names 

 bestowed upon animals in the " Zoo " ever be adopted in 

 general works of travel, we might expect to find such 

 truthful anecdotes as the following : — 



" The insolent behaviour of one of the animals con- 

 siderably annoyed us, from its persistent habit of making 

 ' long noses ' at us. On shooting a specimen we dis- 

 covered that it was a Rude Fox(C«///'.y rudis)j' &c.,&c. 



" Some interesting little creatures now came in sight, 

 dancing, apparently in perfect time, across the glade. 

 They proved to be Pleasant Antelopes {Tragelaphus 

 gratus)," &c, &c. 



" Just as I was emerging from a thicket I managed to 

 trip over something which brought me heavily to the 

 ground. I fancied that I had fallen over a ttee-stump, 

 but on careful examination, it proved to be an Incon- 

 venient Curassow [Crax incominoda) which had somehow 

 got in my way," &c, &c. 



. In his useful little work, a " Key List to British Birds," 

 Colonel Irby has supplied a real want— a handy pocket- 

 book, giving just the diagnostic characters of every 

 species. It is a desirable supplement to the "List of 

 British Birds" published by the British Ornithologists' 

 Union, which dealt with the nomenclature of the various 

 species, but which might also with advantage have con- 

 tained diagnoses, such as Colonel Irby's industry has now 

 supplied. 



What Colonel Irby has done for the birds, Mr. Miller 

 Christy does for the eggs of British birds, and it is certain 

 that with this little work in his hands the young student 

 can gain a very good idea of the eggs which are likely to 

 be met with in England. The call for this second edition 

 of the late Mr. Newman's work shows apparently that 

 there are a good many egg-collectors in this country, 

 notwithstanding the prohibitions of an Act of Parliament ; 

 nor can we state with truth that there is any falling oft" in 

 the number of students of the egg-collection in the British 

 Museum since the Wild Birds Preservation Act became law. 

 To the chapter on bird-skinning we would add a practical 

 hint that before commencing operations a tiny wisp of 

 wool should be inserted into the palate of the specimen. 

 This greatly prevents the risk of discharge from the 

 nostrils, and saves many a skin from being draggled and 

 spoilt. The American method of enveloping the prepared 

 skin in wadding is also far preferable to our method of 

 fastening a paper band round the specimen. 



R. BOWDLKR SHARPE. 



OUR BOOK SHELF. 



Mechanics. By Edward Aveling, D.Sc. (London : 

 Chapman and Hall, Limited, 1888)., 



Tins is the first of four treatises on mechanics and 

 experimental science, published to meet the requirements 

 ot candidates) in the matriculation examination of London 

 University. The volume before us contains a great 

 number of numerical examples and exercises for students, 

 and twenty jages are devoted to specimen examination 



