September 6, 1906] 



NATURE 



463 



There is one more observation made by Hr. Muir 

 (p. 2qo) whicli is rattier puzzling. After R'ving- some 

 identities of Lagranffe's, which are, in fact, relations 

 l>ci\\oen determinants, Dr. Muir says, "a reference 

 til the original pajK-rs, already described, will make 

 it almost perfectly certain that Lagrange did not view 

 them in this light. The like is true of Gauss. . . ." 

 Now Gauss, at any rate, used the term " deter- 

 minant"; if this word is used in the modern sense 

 of the symbol, of course Dr. Muir's remark is correct, 

 but is then quite trivial; on the other hand, if it 

 means the function, it is hard to see how Gauss, not 

 to say Lagrange, could fail to see that their ex- 

 ]5res>ions involved determinants, especially as each was 

 cjuite familiar with ihem in connection with the theory 

 of numbers. This is particularly true of Gauss, who 

 gives the name " determinant " to (067) as well as 

 to (a/3). 



It is a matter of regret that, although a biblio- 

 graphy of orthogonants (to 1840) has b^en given. Dr. 

 Muir has not bc-en able lo include in this volume his 

 valuable lists of writings relating to determinants. 

 To have added them would not have increased the 

 >ize of the book very much, and it would have been 

 very convenient to have them here. But perhaps the 

 author intends to give us the history of his favourite 

 subject subsequent to 1S41, the date at which he has 

 jiiiw closed. G. B. M. 



EUROPEAN VERTEBRATES. 



Die wirbeltliicre Europa's init Beriicksichtigiing der 

 Fauncn von Vorderasien und Nordafrika. By Dr. 

 O. Schmiedeknecht. Pp. vi + 470. (Jena : Gustav 

 Fischer, igo6.) Price 10 marks. 



IT is always convenient to have within covers 

 separated by a moderate distance only an account 

 of the fauna of a definite district, especially when, as 

 in the present instance, the fauna is one that is fairly 

 ■exhaustively known. It is not likely that a manual 

 of the scope of that which we review here will ever 

 need substantial alteration, or even slight changes, 

 for many years to come. The volume, in fact, is not 

 only of permanent value, but contains the marrow 

 of a whole library of faunistic works, and includes all 

 that the student needs, whether the aim of his studies 

 be purely geographical or whether he desires a handy 

 series of definitions of families, genera, and species. 

 Inasmuch as the volume is something less than five 

 hundred pages in length, and seeing that the defini- 

 tions of family and other characters are often from 

 twelve to twenty lines in length, the author is com- 

 pelled to deny himself any discussion of points round 

 which opinions fluctuate, and is driven to be entirely 

 dogmatic. 



It is therefore not everyone who will follow Dr. 

 Schmiedeknecht with complete agreement from 

 beginning to end. He will not, for example, please 

 all of us by placing the " reed pheasant," Paiiurus 

 biarmicHs, among the tits, though it is frequently 

 •called the bearded tit ; nor can we agree to the use 

 NO. 1923, VOL. 74] 



of four separate generic names for the four species of 

 rorquals, which appears to us as a recrudescence of 

 one of the very worst achie%'ements of the systematists 

 of the past. In adopting an old scheme of arrange- 

 ment for birds, the author is compelled thereby to 

 separate widely the gulls and I.imicoline birds, which 

 many anatomists have concurred in placing in very 

 close relationship. There arc plenty of similar 

 examples lo be gathered from Dr. Schmiedcknecht's 

 pages. If the author errs at all in the number of 

 species which he admits into his manual, it is rather 

 on the side of economy than profusion. Of the very 

 long series of "species" of mice admitted, or rather' 

 insisted upon, by some British naturalists, Dr. 

 Schmiedeknecht will only consider four as established. 

 Perhaps he carries this plan a little too far in de- 

 clining to admit the " Irish weasel," Mustela 

 Iiibernica, which is not in :uiy way referred to. 

 .\propos of weasels, it will certainly surprise some 

 persons to learn that the proper name of the common 

 weasel is not Mustela vulgaris, but M. nivalis, inas- 

 much as (according to Dr. Schmiedeknecht) Linnaeus 

 gave the name to an individual in winter dress. 



That the weasel, like its very close ally the stoat, 

 changes to white in winter can hardly be a fact of 

 general knowledge, since it is not mentioned in at 

 any. rate one well-known work upon British 

 mammals. 



In classifying the snakes. Dr. Schmiedeknecht 

 follows a somewhat curious plan. He divides the 

 European species into five families of equal rank, 

 which are (in the order treated by him) Crotalidse, 

 Viperidae, Colubridae, Peropodidas, and Typhlopidae. 

 To give the " pit vipers " a place in the system whicli 

 divides them as far from the more typical Viperida- 

 as from the Peropodidae, or Boidae as most would 

 prefer to call them, is quite opposed to the minute 

 details of anatomical agreement between all vipers. 



To such criticisms, however, the author might well 

 reply that his arrangement is rather a sorting than a 

 classification, and that, as a matter of fact, judged 

 by external characters only (and it is these alone that 

 are made use of), the two divisions of the vipers are 

 very distinct, and the gulls are remote from the sand- 

 pipers, plovers, &c. 



In his preface. Dr. Schmiedeknecht puts himself 

 forward as a champion of the systematic aspect of 

 zoology as a desirable commencement for the student 

 of that science There is no doubt that most of us, in 

 this country at least, were led to pursue zoological 

 studies by reason of the fervour and enthusiasm 

 engendered by the joys of collecting objects of natural 

 history. The quality of knowledge possessed by the 

 pure systematist of mature years is often but little 

 in advance of this stage, and in remarking that " he 

 must be as a rule a remarkable systematist who is 

 not at the same time a biologist," the author is ex- 

 pressing an opinion which the annals of museums do 

 not confirm. In fact. Dr. Schmiedcknecht's intro- 

 ductory remarks read a little like an apology, which is 

 not at all needed in introducing so useful and accurate 

 a work as that which we notice here. F. E. B. 



